Disappointing DT chrono today from my G20 !!! [Archive] - Glock Talk

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alpha6164
07-30-2010, 16:34
So have been meaning take my G20 to the range for sometime to check some numbers and compare DT to some of the other 10mm i have piled up. I just purchased a nice Chrono at Midway and decided to try it out. Weather was 93deg today so definitely nothing that should limit velocity.


I am just going to list the average of 5 shot string from each load.

DT 135gr = 1463 ft/sec
DT 200gr XTP= 1089 ft/sec
DT 180 XTP = 1211 ft/sec

Win Silvertips 175gr = 1189ft/sec
Federal Hydra 180gr = 1070ft/sec


For comparison i also chrono'd some 9mm and 5.56 rounds and those numbers were right on to where they are supposed to be so it is not a equipment issue..

Out of M&P 9mm compact

Federal HST 147gr = 950 ft/sec
Federal HST 124gr +P= 1135 ft/sec
Ranger T 147gr = 946 ft/sec
Corbon DPX 125gr = 1130


Out of 14.5" barrel Noveske=

Privi M193 55gr = 3042 ft/sec
XM193 55gr = 3056 ft/sec
Brown Bear 62gr = 2780 ft/sec
Silver Bear 62gr = 2777 ft/sec


The DT rounds are significantly slower than "advertised" numbers. I understand that the loads i have are not currently available. Since it looks like DT no longer uses GD or XTP bullets. But i doubt the velocities listed currently should be much different for same bullet weight.

DT shows 1600ft/sec for their 135gr and 1300ft/sec for their 180gr and my numbers are way off. They dont even show the 200gr hollow point anymore. The Win Silvertips peformed basically identical velocity wise compared to the DTs.

Also, any thoughts on the current line up of DT 10mm ammo? Are they still the go to guys for 10mm since they no longer carry the GD or XTP? All inputs appreciated.

jeffreybehr
07-30-2010, 17:02
Which chronograf?

How far away did you place the screens?

Did you correct to muzzle velocity?

Barrel length?

PATRICE
07-30-2010, 17:05
.....

alpha6164
07-30-2010, 17:27
Which chronograf?

How far away did you place the screens?

Did you correct to muzzle velocity?

Barrel length?




I got the Competition Pro from Midway. It has gotten a lot of positive reviews. The screens are a fixed distance apart from each other. I stood 7feet back. I never got an error during the entire session. I did not correct anything, i doubt that at 7ft velocity will drop more than a couple of feet. I have the standard Glock 20 so standard barrel which is what is listed on DT website.


It can not be equipment (chrono) because both my 9mm and AR which obviously have huge differences in velocity range were right on the money.

Kegs
07-30-2010, 18:06
DT shows 1600ft/sec for their 135gr and 1300ft/sec for their 180gr and my numbers are way off. They dont even show the 200gr hollow point anymore. The Win Silvertips peformed basically identical velocity wise compared to the DTs.

Also, any thoughts on the current line up of DT 10mm ammo? Are they still the go to guys for 10mm since they no longer carry the GD or XTP? All inputs appreciated.

As a former customer, I remain unimpressed.

I am very impressed with all the reloading and testing that Mike McNett shared here on Glock talk, and I have no doubt that he is one of the most knowledgeable people there is concerning loading the 10mm cartridge. I think he has a very good idea of what limits stock 10mm chambered firearms can take, but the bottom line is that whenever anyone has tested Double Tap ammo against a chronometer out of their personal gun, the velocities come up short - based on what has been posted on this forum.

I am very much looking forward to the day when I can purchase a chronometer so I can compare the rounds I have to my handloads. I will be surprised if my 200gr. xtp handloads (even the ones below max published #s) don't perform superior to the rounds I purchased from Double Tap in both high velocity and consistent velocity (and I'm only using amateur equipment + stock primers, powders, etc.

As you can see in this picture, Double tap clearly stated the published velocity on the side of their 200 gr. xtp (SIC! These are Montana Gold bullets) "controlled expansion" bullets.

http://i65.photobucket.com/albums/h235/Radsport2er/Newconfiguration.jpg

ronin.45
07-30-2010, 18:37
I have heard many issued with DT over the last couple years. It has definitely turned me off of the company. I will deal with Buffalo Bore instead.

chippy
07-31-2010, 10:55
Isn't Buffalo Bore using the same MT.Glod bullet in their 10mm 180grn hp load - for a lot more money? DT is still the better ammo, I just wish they would go back to premium bullets. XTP and GD .40 bullets are in short supply.
Better to "roll your own", if you can find the projectiles!

Taterhead
07-31-2010, 11:53
The last 180 gr BB that I bought had MG bullets. They did not put GDHP on the box though so not misleading.

TransAm-98
07-31-2010, 13:08
Hmm, I just came on here to see if there was any new info on DT ammo cause I was thinking about ordereing some more. And wouldn't you know, it's the first thread I see. I've been using Georgia Arms for plinking but I have a small stock pile of DT ammo from a couple years ago for defensive ammo and when I want to practice witha little more power. I was thinking about restocking on the DT but maybe I'll hold off, as this isn't the first thread I've read with complaints about them recently.

I recently got a "Hammie Down" Dillon SDB so maybe it's time to gear up, do my research and get to reloading.

Angry Fist
07-31-2010, 14:24
Anyone chrono DT's 155gr. BarnesTAC XP? It's my carry load, and said to go 1400... :dunno:

SDGlock23
07-31-2010, 14:57
Join the crowd. I posted a long time back the low numbers I got out of my G20. If I remember right, the 200gr WFNGC did about 1100 FPS (DT claims 1300!). 180gr Gold Dots did the best, around 1250, only 50 fps off. The 155gr Gold Dots did just over 1300 fps (DT claims 1475!). Not terrible compared to some other 10mm loadings, but when you pay velocity, which is essentially what DT is, then you should get it, or at least reasonably close. I can get those numbers using the .40.

However, I did manage to Chrono some DT 357 SIG 115gr Gold Dot and they actually averaged faster than what DT claimed! But in reality, you can expect to get a bit less velocity than what the box says, even with the major manufacturers. Reloading is about the only sure way to really get what you want out of any given cartridge.

glocknick
07-31-2010, 17:20
i think most of us on glock talk are former customers. i can deal with fraudulent velocities inflated to help sell the product. i just cant deal with a company that labeled a box of ammo with 200grain controlled expansion and send me 180 grain montana golds. i refuse to use any of there ammo for self defense and wont purchase again from them once i use up the last couple of boxes i have.

527varmint
07-31-2010, 19:47
problem is double tap is about the only show in town.

gatorboy
08-01-2010, 08:46
I've come to expect the #'s are slightly inflated. I've been shooting it since he opened for business in 2004, I think. It may have been a bit hotter then but getting sued for something or other is always something a good business owner is going to consider. BB does seem to live up to it's #'s. Without a chrono, you could expect DT #'s to match up with Corbon's for weight at a much better deal in nickle plated brass. I have a hard time believing the Barnes load ballistics. That stuff is softer shooting than .40. It makes an excellent SD choice in 10mm IMO.

cowboywannabe
08-01-2010, 15:38
problem is double tap is about the only show in town.

this is true to a point. BB and Cor-Bon make $1+ per round 10mm ammo that is supposed to be a descent h.p. bullet and true or near true speeds.

there are quite a few fly by night companies that go in and out of business (production) periodically....swap fox, elite ammunition, grizzly......none stay in the game long, usually man power, supply problems, personal illness or problems with help, they are small companies sometimes one man deals....so it doesnt take much to put them **** up.

even Reeds ammo which is surprisingly reputable for a small time operation has problems with 10mm componants.

none of the "big three" care enough to do the 10mm properly, and it seems DT has joined them.

cmspeedy
08-01-2010, 17:25
Where have you been? People have been complaining about DT's velocity numbers for a while. I won't ever shoot it again after the dangerous looking smileys I had on some of his 165GD loads - the closest I ever came to a blow out.

I now shoot handloads exclusively and push a 180gr XTP anywhere from 1200-1290fps with 9.1-9.4gr of longshot and 1.260 OAL. My load I make most frequently is 9.3 gr longshot which averages about 1260fps. Absolutely zero signs of overpressure, no smileys and 100% consistent through over 500 rounds now.

If you like the 10mm my advice is to start reloading. Doubletap is no longer a viable option to many of us 10mm lovers and Buffalo Bore is overpriced and is substituting bullets.

The only commercial load I like is the corbon DPX - out of the G20 there is very little recoil and the x-tac is a great performing bullet. My next endeavor is to buy some xtacs and experiment with longshot. Not much data out yet for these bullets.

vaquero aleman
08-01-2010, 18:57
I've often wondered why the GA Arms 165gn @ 1250fps had as much kick as the DT 135gn @ 1600fps. I guess it's all coming to light now!

cmspeedy
08-02-2010, 05:15
The recoil of the 135 is so light that i GREATLY doubt it is close to 1600fps. I havent chronoed their crap lately because i prefer retaining all of my fingers. Quality control from DT has been getting scary.

Has anyone handloaded xtacs yet. Recipes? I dont think they need to hit 1400fps to be effective. Corbon loads them to 1200. You may not gain much overdriving these rounds. I love the very light recoil. Velocity window?

cowboywannabe
08-02-2010, 06:38
bullet design and all that jazz aside, id like to find a reputable company that sells affordable 10mm at the original specs, 170gr. @ 1400 fps, 200gr. @1200 fps. those numbers were from a stock gun 5" bbl.

if Win STHP was anywhere close to their claims it'd be a good 10mm round instead of a .40cal round in a 10mm package, and Rem. and Fed dont even come close either.

Cor-Bon is semi close but very expensive, and BB is expensive and only offers heavy loads best suited for hunting.

cwb
08-02-2010, 08:29
problem is double tap is about the only show in town.
Hardly.

cheez
08-02-2010, 18:09
I read these threads about eroneous DT velocities on several boards. One thing I have yet to read though is a response from Double Tap. Has anyone that has chronographed their loads contacted the company for an explaination? My experience has been nothing but positive from Double Tap and I would think that Mike would be happy to address complaints.

Jumper
08-02-2010, 19:34
There are variances in chronographs especially when used with natural lighting.
When McNett was developing his 10mm loads here on the 10 Ring, he was using an Oehler 35 ballistic explorer. Thats probably the best chrono that can be bought by mere mortals. Depending on what chrono the OP was using could have a big effect on reported velocities.

I know this; I chronographed DT 165gr loads over my CED Millenium and got velocities very close to the advertised velocities. Double Tap Ammo is good to go in my book.

Angry Fist
08-02-2010, 19:56
I still carry the 155 Barnes, because (without much research) I don't know who else loads that. High speed, huge cavity, perfect expansion and weight retention. What else am I to do?

alpha6164
08-03-2010, 08:29
I read these threads about eroneous DT velocities on several boards. One thing I have yet to read though is a response from Double Tap. Has anyone that has chronographed their loads contacted the company for an explaination? My experience has been nothing but positive from Double Tap and I would think that Mike would be happy to address complaints.


This would only make sense if all my chorono readings were off. In the same session i also chronod several other ammo and guns for my own good and all were right on the money. My 9mm 147gr Federal HST chrono'd at 951ft/sec out of M&P9c and Federal XM193 55gr showed 3032 ft/sec out of a 14.5" barrel during the same sitting. This shows that the chrono is reading right.

Jumper
08-03-2010, 11:51
This would only make sense if all my chorono readings were off. In the same session i also chronod several other ammo and guns for my own good and all were right on the money. My 9mm 147gr Federal HST chrono'd at 951ft/sec out of M&P9c and Federal XM193 55gr showed 3032 ft/sec out of a 14.5" barrel during the same sitting. This shows that the chrono is reading right.

Can you post the entire shot string numbers instead of just the average?

alpha6164
08-03-2010, 11:54
Can you post the entire shot string numbers instead of just the average?



I dont have them at hand, i am at work. But there was nothing extreme. From whatever the average is posted the shot strings were up and down 10-15f/sec. I would say that shot to shot variance was in the 20-30range.

cowboywannabe
08-03-2010, 12:47
of the DT rounds ive shot but not chrono'ed, they all seemed a bit more stout than the other over the counter 10mm h.p. ive gotten from Win STHP, PMC Starfire, and a host of FMJ stuff.

of course without a chronograph i cant say the DT was stouter because it was up to the advertized velocities or that ALL the ammo was slower than listed and the DT was just a bit more than them....

2c5s
08-03-2010, 14:08
I read these threads about eroneous DT velocities on several boards. One thing I have yet to read though is a response from Double Tap. Has anyone that has chronographed their loads contacted the company for an explaination? My experience has been nothing but positive from Double Tap and I would think that Mike would be happy to address complaints.

Well, after three phone calls to DT asking for Mike and or a return call, I finally just emailed him. His responce......"Try backing to at least 15ft from the chrono. You can get skewed results if closer. Thanks.". Hmmm, the other factory ammo that shot as advertised didn't mind being 5 ft. from the chrony.

My results form last month:

Fired 5ft. from chrony. It took me 30 minutes to test. DA was 2,382 at the start, and 2,483 at the end of the test.
All 10mm and 9x25: Glock 20. .45acp from a 5" 1911, 9mm out of a Sig 226, .357sig Glock 33. All factory barrels except the 9x25, LW.

9x25 95 gr. Adv. 1990 fps
1. 1779 Dev. 27 fps
2. 1762
3. 1782
4. 1759
5. 1755
AVG. 1767 -11% from Adv.

9x25 147 gr. Adv. 1495 fps
1. 1251 Dev. 30 fps
2. 1227
3. 1230
4. 1237
5. 1221
AVG. 1233 -17% from Adv.

10mm 165 gr. Georgia Arms Adv. 1250 fps
1. 1229 Dev. 23 fps
2. 1241
3. 1228
4. 1218
5. 1227
AVG. 1228 -1.5% from Adv.

10mm 180 gr. Nosler JHP Adv. 1305 fps
1. 1210 Dev. 53 fps
2. 1237
3. 1189
4. 1204
5. 1184
AVG. 1204 -8% from Adv.

10mm 150 gr. Nosler JHP Adv. 1475 fps
1. 1405 Dev. 84 fps
2. 1346
3. 1321
4. 1344
5. 1385
AVG. 1360 -8% from Adv.

10mm 165 gr. Bonded Def. JHP Adv. 1400 fps
1. 1294 Dev. 52 fps
2. 1242
3. 1256
4. 1267
5. 1250
AVG. 1261 -10% from Adv.

10mm 200 gr. WFNGC Adv. 1300 fps
1. 1139 Dev. 20 fps
2. 1133
3. 1135
4. 1144
5. 1153
AVG. 1140 -12% from Adv.

10mm 135 gr. Nosler JHP Adv. 1608 fps
1. 1459 Dev. 89 fps
2. 1453
3. 1475
4. 1427
5. 1516
AVG. 1466 -9% from Adv.

10mm 165 gr. Golden Saber Adv. 1425 fps
1. 1321 Dev. 51fps
2. 1321
3. 1314
4. 1338
5. 1287
AVG. 1316 -8% from Adv.

.45 ACP 185 gr. Gold Dot Adv. 1225 fps
1. 1299 Dev. 242 fps
2. 1159
3. 1091
4. 1057
5. 1203
AVG. 1161 -5% from Adv.

9mm 124 gr. Bonded Defense Adv. 1310 fps
1. 1222 Dev 43 fps
2. 1210
3. 1206
4. 1198
5. 1179
AVG. 1203 -7% from Adv.

.357 SIG 125 gr. Bonded Defense Adv. 1450 fps
1. 1342 Dev. 68 fps
2. 1372
3. 1368
4. 1304
5. 1307
AVG. 1338 -8% from Adv.

2c5s
08-03-2010, 14:12
So have been meaning take my G20 to the range for sometime to check some numbers and compare DT to some of the other 10mm i have piled up. I just purchased a nice Chrono at Midway and decided to try it out. Weather was 93deg today so definitely nothing that should limit velocity.


I am just going to list the average of 5 shot string from each load.

DT 135gr = 1463 ft/sec
DT 200gr XTP= 1089 ft/sec
DT 180 XTP = 1211 ft/sec



Funny how my avg's. are almost exactly the same as yours.

135 gr. = 1,466
200 gr. = 1,140
180 gr. = 1,204

DT has seen the last $ from me, that's for sure.

cowboywannabe
08-03-2010, 14:32
Funny how my avg's. are almost exactly the same as yours.

135 gr. = 1,466
200 gr. = 1,140
180 gr. = 1,204

DT has seen the last $ from me, that's for sure.

there are plenty of neophytes to bite on the 10mm loading and DT hype. they will take your place and you wont be missed....sadly.

Angry Fist
08-03-2010, 15:38
10mm 165 gr. Georgia Arms Adv. 1250 fps
1. 1229 Dev. 23 fps
2. 1241
3. 1228
4. 1218
5. 1227
AVG. 1228 -1.5% from Adv.


GA, according to your data, is the only load even close to it's advertised velocity... interesting.

gatorboy
08-03-2010, 17:16
2c5s - Is the 9x25 barrel you used 4.5" or 6"? Thanks in advance.

Colorado4Wheel
08-03-2010, 17:26
I can't believe you guys actually believed his hyped up numbers to begin with..

2c5s
08-03-2010, 17:42
2c5s - is the 9x25 barrel you used 4.5" or 6"? Thanks in advance.

5"...

Jumper
08-04-2010, 18:13
I set my chrono up today to check the velocity of 2 Double Tap loads that I had on hand. My Chronograph is a CED Millenium with Infrared sky screens. The IR skyscreens provide consistent illumination for both sensors and have made a noticeable improvement in the consistency of my results since I started using them.

The gun was a G20 with a 4.6" (standard length) EFK barrel. The same gun and barrel length DoubleTap lists for their advertised velocity for these rounds.

Conditions were overcast, 84 deg F, 48% humidity and 29.74in/HG.

I set up the screens and MEASURED 10ft from the center of the screens and fired the first string with some of my handloads just to get things set up. Here is the results of that string:

Millennium Data Collector - 8/4/10
( = flyers, * = deleted shots)

GROUP #1 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 10ft from center of screens.
1)1139.0 -413.4
2)1628.0 75.6
3)1573.0 20.6
4)1521.0 -31.4
5)1240.0 -312.4
6)1348.0 -204.4
7)1004.0 -548.4
8)1743.0 190.6
9)1854.0 301.6
10)2474.0 921.6
High: 2474.0
Low: 1004.0
E.S.: 1470.0
Ave.: 1552.4
S.D.: 420.8
95%: 261.0

I checked the display as I shot and was pretty consistently getting very erratic numbers. I omitted 2 shots that read over 2500fps. Notice shot #10 that I did not omit. Notice also the wild readings for several other shots. This ammo was made using IMR800-X which meters very poorly and significant deviation within about 100fps has been typical in the past. But not this bad. The reason was I was too close to the screens and the muzzle blast was reaching the screens and causing the errant readings.

I backed up to 12ft and tried again with the same load:

GROUP #2 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 12ft from center of screens.
1)1987.0 910.4
2) 305.4 -771.2
3) 834.0 -242.6
4)1104.0 27.4
5)1153.0 76.4
High: 1987.0
Low: 305.4
E.S.: 1681.6
Ave.: 1076.6
S.D.: 610.0
95%: 535.0
I still got errant readings but better than the 10ft distance. I backed up to 15ft (the distance recommended by McNett ant Double Tap) and tried again:

GROUP #3 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 15ft from center of screens.
1)1120.0 -13.4
2)1135.0 1.6
3)1221.0 87.6
4)1056.0 -77.4
5)1230.0 96.6
6)1222.0 88.6
7)1080.0 -53.4
8)1086.0 -47.4
9)1097.0 -36.4
10)1103.0 -30.4
11)1119.0 -14.4
High: 1230.0
Low: 1056.0
E.S.: 174.0
Ave.: 1133.4
S.D.: 62.0

15ft provided consistent readings. Next loads I tried were Double Tap, 180gr Gold Dot HP:
GROUP #4 Double Tap 180 Gold Dot JHP; 15ft from center of screens. Advertised MV 1400fps
1)1363.0 7.0
2)1325.0 -31.0
3)1365.0 9.0
4)1351.0 -5.0
5)1374.0 18.0
6)1385.0 29.0
7)1380.0 24.0
8)1338.0 -18.0
9)1323.0 -33.0
10)1361.0 5.0
11)1345.0 -11.0
12)1362.0 6.0
High: 1385.0
Low: 1323.0
E.S.: 62.0
Ave.: 1356.0
S.D.: 20.0
95%: 11.0
95%: 37.0

The advertised velocity from DT is 1400fps and you can see my average was 1356 for 12 rounds. I entered this bullet weight and velocity data into JBM ballistic calculator using a Hornady XTP and it calculated a Muzzle Velocity of 1371 fps. With all the potential variables present I think that an advertised velocity of 1400fps is not unreasonable. Indeed shots 6 and 7 were 1385 and 1380fps - 15ft from the muzzle!

Next up were DT's 165gr Brass Jacketed HP:

GROUP #5 DoubleTap 165gr BrassJHP(Golden Sabre); 15ft from center of screens.
Advertised MV 1425fps
1)1318.0 -14.4
2)1353.0 20.6
3)1311.0 -21.4
4)1324.0 -8.4
5)1326.0 -6.4
6)1371.0 38.6
7)1382.0 49.6
8)1332.0 -0.4
9)1292.0 -40.4
10)1307.0 -25.4
11)1294.0 -38.4
12)1368.0 35.6
13)1345.0 12.6
High: 1382.0
Low: 1292.0
E.S.: 90.0
Ave.: 1332.4
S.D.: 29.2
95%: 16.0

DT's advertised velocity for these rounds is 1425fps. As you can see, at 15ft from the muzzle they were clocked at an average velocity of 1332fps. JBM calculated a Muzzle Velocity of 1350fps using a Sierra 165 gr bullet, about 75fps less than advertised. Again, with all the variables present and allowing for some lot-to-lot variation I don't think there is any reason to doubt DT's velocity claims for their ammo.

Jumper
08-04-2010, 18:24
Well, after three phone calls to DT asking for Mike and or a return call, I finally just emailed him. His responce......"Try backing to at least 15ft from the chrono. You can get skewed results if closer. Thanks.". Hmmm, the other factory ammo that shot as advertised didn't mind being 5 ft. from the chrony.

My results form last month:

Fired 5ft. from chrony. It took me 30 minutes to test. DA was 2,382 at the start, and 2,483 at the end of the test.
All 10mm and 9x25: Glock 20. .45acp from a 5" 1911, 9mm out of a Sig 226, .357sig Glock 33. All factory barrels except the 9x25, LW.

9x25 95 gr. Adv. 1990 fps
1. 1779 Dev. 27 fps
2. 1762
3. 1782
4. 1759
5. 1755
AVG. 1767 -11% from Adv.

9x25 147 gr. Adv. 1495 fps
1. 1251 Dev. 30 fps
2. 1227
3. 1230
4. 1237
5. 1221
AVG. 1233 -17% from Adv.

10mm 165 gr. Georgia Arms Adv. 1250 fps
1. 1229 Dev. 23 fps
2. 1241
3. 1228
4. 1218
5. 1227
AVG. 1228 -1.5% from Adv.

10mm 180 gr. Nosler JHP Adv. 1305 fps
1. 1210 Dev. 53 fps
2. 1237
3. 1189
4. 1204
5. 1184
AVG. 1204 -8% from Adv.

10mm 150 gr. Nosler JHP Adv. 1475 fps
1. 1405 Dev. 84 fps
2. 1346
3. 1321
4. 1344
5. 1385
AVG. 1360 -8% from Adv.

10mm 165 gr. Bonded Def. JHP Adv. 1400 fps
1. 1294 Dev. 52 fps
2. 1242
3. 1256
4. 1267
5. 1250
AVG. 1261 -10% from Adv.

10mm 200 gr. WFNGC Adv. 1300 fps
1. 1139 Dev. 20 fps
2. 1133
3. 1135
4. 1144
5. 1153
AVG. 1140 -12% from Adv.

10mm 135 gr. Nosler JHP Adv. 1608 fps
1. 1459 Dev. 89 fps
2. 1453
3. 1475
4. 1427
5. 1516
AVG. 1466 -9% from Adv.

10mm 165 gr. Golden Saber Adv. 1425 fps
1. 1321 Dev. 51fps
2. 1321
3. 1314
4. 1338
5. 1287
AVG. 1316 -8% from Adv.

.45 ACP 185 gr. Gold Dot Adv. 1225 fps
1. 1299 Dev. 242 fps
2. 1159
3. 1091
4. 1057
5. 1203
AVG. 1161 -5% from Adv.

9mm 124 gr. Bonded Defense Adv. 1310 fps
1. 1222 Dev 43 fps
2. 1210
3. 1206
4. 1198
5. 1179
AVG. 1203 -7% from Adv.

.357 SIG 125 gr. Bonded Defense Adv. 1450 fps
1. 1342 Dev. 68 fps
2. 1372
3. 1368
4. 1304
5. 1307
AVG. 1338 -8% from Adv.

At 5 feet from the chronograph I am almost positive you were clocking muzzle blast. It WILL significantly skew your results.

2c5s
08-04-2010, 18:30
At 5 feet from the chronograph I am almost positive you were clocking muzzle blast. It WILL significantly skew your results.

I will retest shortly.

Kegs
08-04-2010, 19:35
GROUP #3 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 15ft from center of screens.
1)1120.0 -13.4
2)1135.0 1.6
3)1221.0 87.6
4)1056.0 -77.4
5)1230.0 96.6
6)1222.0 88.6
7)1080.0 -53.4
8)1086.0 -47.4
9)1097.0 -36.4
10)1103.0 -30.4
11)1119.0 -14.4
High: 1230.0
Low: 1056.0
E.S.: 174.0
Ave.: 1133.4
S.D.: 62.0

15ft provided consistent readings.



In what world?

Again, with all the variables present and allowing for some lot-to-lot variation I don't think there is any reason to doubt DT's velocity claims for their ammo.In my opinion, your figures show that either 1. your chrono is inoperable, and/or 2., there are some serious quality control problems with your handloads.

Based on the large spread your chrono read on D.T. ammo, I believe it is actually BOTH.

If you take a look at 2c5s's #s, they are far more consistent reads than your own(the gold dot .45 ammo is the anomaly - old perhaps?). At that distance, he may have been measuring muzzle blast, but his spread is more reasonable and in line with factory ammo, which uses fairly tight tolerances.

I would suggest testing that chrono with a rimfire using eley tenex out of a rifle - the chrono should read spreads of less than 10fps - typical is 4 or 5 in 10 samples. If you are reading wild spreads like what you have above for the D.T. test, you need to contact the mfgr.

Jumper
08-04-2010, 19:59
In what world?

In my opinion, your figures show that either 1. your chrono is inoperable, and/or 2., there are some serious quality control problems with your handloads.

Based on the large spread your chrono read on D.T. ammo, I believe it is actually BOTH.

If you take a look at 2c5s's #s, they are far more consistent reads than your own(the gold dot .45 ammo is the anomaly - old perhaps?). At that distance, he may have been measuring muzzle blast, but his spread is more reasonable and in line with factory ammo, which uses fairly tight tolerances.

I would suggest testing that chrono with a rimfire using eley tenex out of a rifle - the chrono should read spreads of less than 10fps - typical is 4 or 5 in 10 samples. If you are reading wild spreads like what you have above for the D.T. test, you need to contact the mfgr.

Consistent readings for the ammo listed. As in my post: the handloads were loaded with an RCBS UNIFLO using IMR800-X. Most handloaders know 800-X meters like corn flakes and you will get significant charge weight variation even throgh an RCBS UNIFLO. The charge weight variation shows up when you chronograph a large sample, exactly like you pointed out. There is nothing wrong with my chrono. And for what these loads were meant for (plinking) they work as intended.

Cam Cooke
08-05-2010, 12:41
I individually weigh all of my IMR800X loads weights thrown are far to inconsistent to load with a powder measure...

cmspeedy
08-05-2010, 15:45
I WILL NOT LOAD 800x with a meter. You are asking for a failure. I don't care if its plinking ammo or any other ammo. With 800X I handload exclusively and it is without any doubts the velocity king of 10mm.

If you want fairly mild velocities, which you would for plinking. Pick up something that meters well and works good in 10mm.

Longshot is my choice and using the same 180g zero hp use 9.1gr to get low 1200s. I measure rounds frequently and using a dillon meter get 9.0- 9.2gr with great consistency.

Powder is cheap - fingers expensive.

My .02

Jumper
08-05-2010, 15:58
I wanted to see just how good or bad IMR800-x would be loading on a progressive press. I knew there was going to be some significant variation and by only loading to 8grs gave what I felt was a good safety margin. As you can see from the extreme spread they varied a lot. Too much to be a valid loading method really. But, if anyone wanted to know how well IMR800-X metered through a Uni-Flo and how much it affected consistency (like I did), there it is.

agtman
08-05-2010, 16:14
I set my chrono up today to check the velocity of 2 Double Tap loads that I had on hand. My Chronograph is a CED Millenium with Infrared sky screens. The IR skyscreens provide consistent illumination for both sensors and have made a noticeable improvement in the consistency of my results since I started using them.

The gun was a G20 with a 4.6" (standard length) EFK barrel. The same gun and barrel length DoubleTap lists for their advertised velocity for these rounds.

Conditions were overcast, 84 deg F, 48% humidity and 29.74in/HG.

I set up the screens and MEASURED 10ft from the center of the screens and fired the first string with some of my handloads just to get things set up. Here is the results of that string:

Millennium Data Collector - 8/4/10
(ƒ = flyers, * = deleted shots)

GROUP #1 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 10ft from center of screens.
1)1139.0 -413.4
2)1628.0 75.6
3)1573.0 20.6
4)1521.0 -31.4
5)1240.0 -312.4
6)1348.0 -204.4
7)1004.0 -548.4
8)1743.0 190.6
9)1854.0 301.6
10)2474.0 921.6ƒ
High: 2474.0
Low: 1004.0
E.S.: 1470.0
Ave.: 1552.4
S.D.: 420.8
95%: 261.0

I checked the display as I shot and was pretty consistently getting very erratic numbers. I omitted 2 shots that read over 2500fps. Notice shot #10 that I did not omit. Notice also the wild readings for several other shots. This ammo was made using IMR800-X which meters very poorly and significant deviation within about 100fps has been typical in the past. But not this bad. The reason was I was too close to the screens and the muzzle blast was reaching the screens and causing the errant readings.

I backed up to 12ft and tried again with the same load:

GROUP #2 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 12ft from center of screens.
1)1987.0 910.4
2) 305.4 -771.2
3) 834.0 -242.6
4)1104.0 27.4
5)1153.0 76.4
High: 1987.0
Low: 305.4
E.S.: 1681.6
Ave.: 1076.6
S.D.: 610.0
95%: 535.0
I still got errant readings but better than the 10ft distance. I backed up to 15ft (the distance recommended by McNett ant Double Tap) and tried again:

GROUP #3 Handloads: Row 137; 180gr ZeroJHP; 8.0gr Imr 800-x; CCI350primer; COL 1.250;
Powder dispensed with an RCBS Uniflo. 15ft from center of screens.
1)1120.0 -13.4
2)1135.0 1.6
3)1221.0 87.6
4)1056.0 -77.4
5)1230.0 96.6
6)1222.0 88.6
7)1080.0 -53.4
8)1086.0 -47.4
9)1097.0 -36.4
10)1103.0 -30.4
11)1119.0 -14.4
High: 1230.0
Low: 1056.0
E.S.: 174.0
Ave.: 1133.4
S.D.: 62.0

15ft provided consistent readings. Next loads I tried were Double Tap, 180gr Gold Dot HP:
GROUP #4 Double Tap 180 Gold Dot JHP; 15ft from center of screens. Advertised MV 1400fps
1)1363.0 7.0
2)1325.0 -31.0
3)1365.0 9.0
4)1351.0 -5.0
5)1374.0 18.0
6)1385.0 29.0
7)1380.0 24.0
8)1338.0 -18.0
9)1323.0 -33.0ƒ
10)1361.0 5.0
11)1345.0 -11.0
12)1362.0 6.0
High: 1385.0
Low: 1323.0
E.S.: 62.0
Ave.: 1356.0
S.D.: 20.0
95%: 11.0
95%: 37.0

The advertised velocity from DT is 1400fps and you can see my average was 1356 for 12 rounds. I entered this bullet weight and velocity data into JBM ballistic calculator using a Hornady XTP and it calculated a Muzzle Velocity of 1371 fps. With all the potential variables present I think that an advertised velocity of 1400fps is not unreasonable. Indeed shots 6 and 7 were 1385 and 1380fps - 15ft from the muzzle!

Next up were DT's 165gr Brass Jacketed HP:

GROUP #5 DoubleTap 165gr BrassJHP(Golden Sabre); 15ft from center of screens.
Advertised MV 1425fps
1)1318.0 -14.4
2)1353.0 20.6
3)1311.0 -21.4
4)1324.0 -8.4
5)1326.0 -6.4
6)1371.0 38.6
7)1382.0 49.6ƒ
8)1332.0 -0.4
9)1292.0 -40.4
10)1307.0 -25.4
11)1294.0 -38.4
12)1368.0 35.6
13)1345.0 12.6
High: 1382.0
Low: 1292.0
E.S.: 90.0
Ave.: 1332.4
S.D.: 29.2
95%: 16.0

DT's advertised velocity for these rounds is 1425fps. As you can see, at 15ft from the muzzle they were clocked at an average velocity of 1332fps. JBM calculated a Muzzle Velocity of 1350fps using a Sierra 165 gr bullet, about 75fps less than advertised. Again, with all the variables present and allowing for some lot-to-lot variation I don't think there is any reason to doubt DT's velocity claims for their ammo.

Jumper, thanks for your hard work and time-expenditure to vet DT's loads.

2c5s' chrono work was done 5-feet from the muzzle and with the 10mm's blast that's sure to skew the results.

If people testing DT 10mm ammo want to get McNett's exact fps/fpe results, then they have to duplicate exactly HIS conditions - no sniveling. :upeyes:

If that's impossible, given variations from McNett's due to the tester's elevation, temp, humidity, barrel-length, poor quality chronograph equipment, improper chrono technique and/or procedure, then the tester has to factor all of that in, given the readings obtained. However, moving back the chronograph equipment to 15-ft isn't impossible.

Any differences or variations that result aren't McNett's fault. :whistling:

:cool:

2c5s
08-07-2010, 08:42
Jumper, thanks for your hard work and time-expenditure to vet DT's loads.

2c5s' chrono work was done 5-feet from the muzzle and with the 10mm's blast that's sure to skew the results.

If people testing DT 10mm ammo want to get McNett's exact fps/fpe results, then they have to duplicate exactly HIS conditions - no sniveling. :upeyes:

If that's impossible, given variations from McNett's due to the tester's elevation, temp, humidity, barrel-length, poor quality chronograph equipment, improper chrono technique and/or procedure, then the tester has to factor all of that in, given the readings obtained. However, moving back the chronograph equipment to 15-ft isn't impossible.

Any differences or variations that result aren't McNett's fault. :whistling:

:cool:


I'm going re-test shortly. I find it interesting that other factory ammo I tested in the same session was spot on to advertised velocity figures. :whistling:

There's no doubt that DT ammo is hotter than most, but it's not what they claim.

We will see, my results will be up shortly.

agtman
08-07-2010, 10:07
I'm going re-test shortly. I find it interesting that other factory ammo I tested in the same session was spot on to advertised velocity figures. :whistling:

There's no doubt that DT ammo is hotter than most, but it's not what they claim.
We will see, my results will be up shortly.

2c5s: don't get me wrong, ... I appreciate that you, Jumper and others here get out and test various 10mm ammo, and then post the results, ... thanks much, as your time & effort benefits us all.

But you're not the first to vet DT's advertised velocity for its 10mm load, as 10mm fans have been posting their finding for a while, starting back about a year or so after he began the business, IIRC. Nor is it just DT 10mm loads. In fact, not too long ago a poster chrono-ed DT's .357Sig loads and reported results that were consistently 50-75fps faster than Mike's "box-flap" velocity. Maybe his were skewed (the other way) too? Who knows?

As Jumper implied in reference to DT's 165gn GS 10mm load, a reading 50-75fps more or less than DT's claimed velocity really isn't going to bother me, since it's still a high-performance load.

I do agree, however, that where you're consistently finding 100-150fps difference from the claimed velocity, and assuming you've duplicated McNett's testing conditions, etc, ... yeah, then he needs to be notified with the specs and lot # of the ammo that was tested and with your results/findings. I would then expect to see some response from him.

:cool:

Cam Cooke
08-07-2010, 12:44
Mcnett was the person that shared his 10mm data then factory loads that gave us the true potential of the 10mm round...

I have nothing but praise for him even if his factory ammo is a bit off its advertised velocities so is every major ammo manufacturer out there...

2c5s
08-07-2010, 18:09
Mcnett was the person that shared his 10mm data then factory loads that gave us the true potential of the 10mm round...

I have nothing but praise for him even if his factory ammo is a bit off its advertised velocities so is every major ammo manufacturer out there...

I for one don't consider DT a major manufacturer. They are a niche catridge company that gets top dollar for their advertised performance. Of which they are falling short.

GA, CB, BB, they achieve their advertised velocity figures. DT is falling short and they know it, they could care less.

cowboywannabe
08-08-2010, 08:09
I for one don't consider DT a major manufacturer. They are a niche catridge company that gets top dollar for their advertised performance. Of which they are falling short.

GA, CB, BB, they achieve their advertised velocity figures. DT is falling short and they know it, they could care less.

you say that like youve rechecked them from 15' away already. what were your results from that outing?

i havent shot BB but i have shot CB and i did not notice a difference between the CB 135gr. and the DT 135 gr. except for the price was about twice as high for the CB. BB of course doesnt make a load lighter than 180 gr. and GA doesnt even prentend to say they load 10mm to true levels.....in fact they load their 180gr. H.P. @ 1150 fps. hardly 10mm stats. they are only a plinking ammo and brass player.

Cam Cooke
08-08-2010, 09:09
Where did I state that they are a major manufacturer I said like every major manufacturer meaning if the big boys do it why do we expect so much more from the little guy?

I've been loading for the 10mm since 1988 but it wasn't until I found Mcnett and his data that I was able to get the velocities I was looking for due to this I totally support his company that I also reload makes it so I am not solely dependant on his products... :tongueout:

agtman
08-08-2010, 10:00
I for one don't consider DT a major manufacturer. They are a niche catridge company that gets top dollar for their advertised performance. Of which they are falling short.

GA, CB, BB, they achieve their advertised velocity figures. DT is falling short and they know it, they could care less.

Actually, GA makes mid-rangish 10mm loads and doesn't care to load to full-strength (high-performance) levels, per the owner to whom I've spoken.

CB's 10mm loads vary. Most of the SD loads are mid-range or tread into upper mid-range for the bullet-weight. Their 200gn "hunting" load appears to be Norma-level, but (per their ballistic tech) they spec their velocities from a 5" test barrel. From a G20's 4.6" tube, that 200gn load is doing 1150fps (again, per the CB tech). Just FYI.

BB does make high-performance 10mm ammo, but the last time I checked they offer exactly two loads - compared to DT, or even CB, which offer way more variety in this caliber. BTW, I've shot both BB 10mm loads and both were full-strength, accurate ammo. My only real beef with BB's 10mm is pricing - for what you pay for a couple of their 20-rd boxes you'll do better with DT's 50-rd boxes, plus there's the shipping factor if you order in volume.

As far as "major manufacturers" go, if you're talking about relative company size, then all those mentioned, plus Hornady and Black Hills (BH), are "niche" ammo producers, none of them being anywhere near the operational size of the big three.

In fact, like DT, BH has been a small family outfit for most of its existence, yet it makes for the U.S. miliary the 5.56mm 77gn OTM (Mk 262 MOD 1) combat load. Pretty prestigious for a small "niche" operation, no? :dunno:

:cool:

alpha6164
08-08-2010, 10:04
UPDATE:


Someone recommended that changing the spring to a heavier will improve my chrono. I ordered the Wolff 24lb spring and guide rod combination.

I took the G20 to the range yesterday and shot the same ammo with the new spring. The conditions were pretty identical, both days in the low 90s temp wise and same humidity. These tests are a week apart so it is right on. Five shot string and posting the average.



Last week with stock barrel and spring: These are average

DT 135gr = 1463 ft/sec
DT 200gr XTP= 1089 ft/sec
DT 180 XTP = 1211 ft/sec


Yesterday with stock barrel and 24lb spring and guide rod: These are average

DT 135gr = 1582 ft/sec
DT 200gr XTP= 1214 ft/sec
DT 180 XTP = 1242 ft/sec


There is no question that 24lb spring helped. What is amazing is that it helped the most with the lightest bullet and in ascending order the heavier the bullet the less it improved with the heavier spring but all improved. I guess that there is so much more pressure/powder in the 135gr load that opens the breach face faster and longer changing the velocity.

Just wanted to post this because it somewhat gets DT off the hook. It is possible that at elevation (i am at seal level) those numbers can be another 50ft/sec faster which would be closer to their advertised data.

cowboywannabe
08-08-2010, 10:48
the stiffer spring holds the slide closed a nano second longer allowing the charge to push the bullet more and the slide less.

i have not used my stock spring for my G20 but have for my G29 and soon got an after market G29 assy. i use 22lbs springs in my guns and they shoot fine.

again, i do not have a chrono, so if DT is slower than advertised then so are the rest because DT seems more stout than the rest, except CB which "seemed" about the same in my stock G29. no more ammo to try it in my "fixed" G29.

alpha, can you get with somebody and check the G29 speeds?

alpha6164
08-08-2010, 11:03
the stiffer spring holds the slide closed a nano second longer allowing the charge to push the bullet more and the slide less.

i have not used my stock spring for my G20 but have for my G29 and soon got an after market G29 assy. i use 22lbs springs in my guns and they shoot fine.

again, i do not have a chrono, so if DT is slower than advertised then so are the rest because DT seems more stout than the rest, except CB which "seemed" about the same in my stock G29. no more ammo to try it in my "fixed" G29.

alpha, can you get with somebody and check the G29 speeds?






I dont know anybody that owns a G29. Trust me i am a hair away from getting a 29SF to add to the family specially now that i am gonna reload. If i do get it i will definitely post some results :)

Kegs
08-08-2010, 13:19
I have a G29 and will obtain a chrono pretty soon. I will be documenting D.T. 200 grain controlled expansion load using my stock barrel/spring compared to the 21# wolff spring/steel rod and both stock barrel and 4.55" KKM bbl.

By the way - the discovery of the heavier spring in the gun showing higher velocities is an excellent one.

Kegs
08-08-2010, 13:28
I WILL NOT LOAD 800x with a meter.


Neither will I.

cowboywannabe
08-08-2010, 16:46
I have a G29 and will obtain a chrono pretty soon. I will be documenting D.T. 200 grain controlled expansion load using my stock barrel/spring compared to the 21# wolff spring/steel rod and both stock barrel and 4.55" KKM bbl.

By the way - the discovery of the heavier spring in the gun showing higher velocities is an excellent one.

and i thought that was common knowledge....the 17# spring being stock for the 10mm just like it is for the 9mm in the G17....spare me the heavier slide stuff folks....thats comparing ounces of slide weight to pounds of force of the stock vs. after-market springs...

its my feeling that Glock decided that the 17 pound spring along with the heavier slide of the G20 was plenty for the run of the mill watered down stuff that Rem. Fed. Win. Hornanday...etc puts out, and theyre right. but this combos is far from optimal for true 10mm powered loads.

David N.
08-08-2010, 17:59
and i thought that was common knowledge....

I thought most 10mm people had heard about it, too. BB states on their website that heavier springs can improve extreme spread. However, in my test, using my G29 (factory and KKM barrel) with the factory spring and all three springs offered by Wolff, I saw no significant difference. The averages of each group of five rounds of BB 180 shot using each spring were all within few fps of each other, and there were no significant differences in extreme spread.

chippy
08-08-2010, 20:45
FWIW- I emailed Mike M. about what weight spring to use with DT ammo. He advised 22#. Works good with hot loads as well as Blazers, just like he said it would. I tried a 24# and had no problems with my reloads. I wouldn't trust it with light loads though. The stock 17# works, but man does it fling the emptys out there!


O.T. - What does a good chrono run these days? Nothing fancy, just the basics.

cowboywannabe
08-08-2010, 20:49
$80.00

Cam Cooke
08-08-2010, 21:04
Get a Shooting Chrony excellent well priced unit I've had one for almost 20 years and just this year sent it back in they credited me the exact amount I paid for it and for $150.00 more sent me their top of the line unit.

Wish I would have just stayed with the base model I don't need no bells and whistles...

chippy
08-08-2010, 21:08
Wish I would have just stayed with the base model I don't need no bells and whistles...


That's what I am thinking

cowboywannabe
08-08-2010, 21:53
look at midway or ctd....they have shooting chronys for about $80.00

chippy
08-08-2010, 22:21
Thanks for the heads up.

Angry Fist
08-08-2010, 23:33
Hell, for $80, it can be a lot more fun, and cheaper than a new barrel. Just shoot everything through it.

Kegs
08-10-2010, 16:46
and i thought that was common knowledge....the 17# spring being stock for the 10mm just like it is for the 9mm in the G17....spare me the heavier slide stuff folks....thats comparing ounces of slide weight to pounds of force of the stock vs. after-market springs...

its my feeling that Glock decided that the 17 pound spring along with the heavier slide of the G20 was plenty for the run of the mill watered down stuff that Rem. Fed. Win. Hornanday...etc puts out, and theyre right. but this combos is far from optimal for true 10mm powered loads.

The underpowered spring is the common knowledge, sure - but the fact that you would get higher velocity out of using a heavier spring? This is the first time I am hearing about that. I'm sure it's been "discovered" before, but like I said- first for me, and I am skeptical - as I always am, so I'm going to test this thing and see what happens for my figures.

...Get ready for the grandaddy of 10mm threads here in the 10 ring...Should have a chrono in a matter of a week or so. I already have 200 rounds to test with - and will load some more shortly thereafter.

MSgt Dotson
08-13-2010, 16:07
The bullet has left the bbl before the locked slide/bbl has recoiled .1" or so to the rear....; I find it hard to believe that a weaker recoil spring allowing the slide to recoil a little more freely/faster 'bleeds off' more than one hundred fps velocity....

Now the chrono does not usually lie; chrono ten rounds with stock spring, chrono ten rounds with heavier spring, chrono with stock spring again....; same day testing, 2 min apart...

MalumProhibitum
08-15-2010, 20:26
http://i65.photobucket.com/albums/h235/Radsport2er/Newconfiguration.jpg
Sorry for the off topic question, but what is that on your magazine in the gun, at the bottom of the grip? Some kind of adapter?

Cam Cooke
08-15-2010, 20:27
That is a G20 mag with a Pearce mag sleeve basically gives you a full size G20SF grip.

I have the same set up for my G29.

MalumProhibitum
08-20-2010, 12:28
UPDATE:


Someone recommended that changing the spring to a heavier will improve my chrono. I ordered the Wolff 24lb spring and guide rod combination.

I took the G20 to the range yesterday and shot the same ammo with the new spring. The conditions were pretty identical, both days in the low 90s temp wise and same humidity. These tests are a week apart so it is right on. Five shot string and posting the average.



Last week with stock barrel and spring: These are average

DT 135gr = 1463 ft/sec
DT 200gr XTP= 1089 ft/sec
DT 180 XTP = 1211 ft/sec


Yesterday with stock barrel and 24lb spring and guide rod: These are average

DT 135gr = 1582 ft/sec
DT 200gr XTP= 1214 ft/sec
DT 180 XTP = 1242 ft/sec


There is no question that 24lb spring helped. What is amazing is that it helped the most with the lightest bullet and in ascending order the heavier the bullet the less it improved with the heavier spring but all improved. I guess that there is so much more pressure/powder in the 135gr load that opens the breach face faster and longer changing the velocity.

Just wanted to post this because it somewhat gets DT off the hook. It is possible that at elevation (i am at seal level) those numbers can be another 50ft/sec faster which would be closer to their advertised data.

I am not sure what to think. This is the most interesting post I have seen in a long, long time.

Kegs
08-28-2010, 19:28
I chronographed 3 double tap rounds today. I had 6 to spare and had 3 misreads - so this is a very small sample...These are listed as 200gr. "controlled expansion" on the box. I have not pulled one of these bullets and confirmed that it is actually 200 gr., but they are montana gold bullets.

Another person had reported that they substituted 180 gr. bullets for these. I will have to run one of these through the milk jugs and weigh it afterward to better get an idea.

At any rate, I ran 50 handloads today - I'll report more on it in a different thread once I have some additional time, but the bottom line is I am using 22lbs. springs and a 4.45" kkm barrel in my G29 (so this is very close to the G20 bbl. length) The D.T. box suggests 1250 fps out of a g20. I found the bullets ran in the high 1100s - around 1180 or so - which is very impressive to say the least if they are indeed 200 gr. bullets, but I do not believe they could reach the 1250 fps level in a stock g20 unless the conditions were favorable for the absolute highest velocities.

I wish I had more ammo to test, but I have since shot most of the D.T. up in the last few months.

They are overrated, but not by much based on the small sample I tested.

Kegs
08-28-2010, 19:35
The bullet has left the bbl before the locked slide/bbl has recoiled .1" or so to the rear....; I find it hard to believe that a weaker recoil spring allowing the slide to recoil a little more freely/faster 'bleeds off' more than one hundred fps velocity....

Now the chrono does not usually lie; chrono ten rounds with stock spring, chrono ten rounds with heavier spring, chrono with stock spring again....; same day testing, 2 min apart...

I am SO going to do this once I have developed a hunting load for this gun...

Meathead9
08-28-2010, 22:43
For what it's worth, I tested 5rds of DT 200gr WFNGC with my Shooting Chrony F1 Master. This was out of a 6" barrel, and using a 22# spring. The box advertises 1300fps out of a 4.6" barrel. This is what I got:

1199, 1220, 1173, 1227, 1216

While a 200gr bullet @ 1200fps is nothing to cry about, I'm a little disappointed because I'm using a 1.4" longer barrel. Before I tested the ammo, I thought for sure I would reach the advertised velocity with the 6" barrel. Next time out I'll run some more rounds through the chrony with my G20L upper, using 17/19/20/22# springs and see if there's a noticeable difference in my gun.

MalumProhibitum
08-29-2010, 05:46
I can't wait to hear all the results of this back to back spring testing.

Kegs
08-29-2010, 08:47
I can't wait to hear all the results of this back to back spring testing.

I might load up 10 rounds of hot blue dot and run 5 with the stock spring on just to see if there is any difference. My suspicion is that there will be little to no difference, but I won't know until I test it.

5 rounds is a very small sample, but I think its enough to get an idea of #1 how fast a max (published) load runs in my rig, and #2 if the spring makes much of a difference in relation to that.

Also: I have been thinking about getting a 24# spring. I think these really hot rounds overrun the 22# a bit. The brass is still flying pretty far even with the 22#.

hypnagogue
08-29-2010, 14:06
Back of the envelope calculations seem to show that the "breech opens too fast" argument is null, at least with the G20 and G29 -- the slide weight is sufficient to keep it locked up until the bullet exits the barrel. Thus any explanation would have to be with slower powders burning slower due to the slide velocity reducing the pressure (unless someone else has an Idea They Would Like To Share). This effect is going to be powder-specific, with fast powders showing almost no effect, and slower powders showing the most.

So, your test with Blue Dot sounds like a good idea, since that is a slow powder. Testing with a G29 is not quite ideal, as the shorter barrel isn't going to get the most from slower powders anyway, but it might show some effect. Unfortunately, your Blue Dot test won't have any relevance with respect to Double Tap ammo, unless we happen to know that Blue Dot is the powder that Mike uses (I think not...).

Kegs
08-29-2010, 20:18
Back of the envelope calculations seem to show that the "breech opens too fast" argument is null, at least with the G20 and G29 -- the slide weight is sufficient to keep it locked up until the bullet exits the barrel. Thus any explanation would have to be with slower powders burning slower due to the slide velocity reducing the pressure (unless someone else has an Idea They Would Like To Share). This effect is going to be powder-specific, with fast powders showing almost no effect, and slower powders showing the most.

So, your test with Blue Dot sounds like a good idea, since that is a slow powder. Testing with a G29 is not quite ideal, as the shorter barrel isn't going to get the most from slower powders anyway, but it might show some effect. Unfortunately, your Blue Dot test won't have any relevance with respect to Double Tap ammo, unless we happen to know that Blue Dot is the powder that Mike uses (I think not...).

Some notes:

First of all, I am using an extended barrel in my G29. It is 4.45" in length. That puts my particular G29 very close to a G20 in barrel length. Certainly, 0.15" is not going to make a significant difference in velocities based on burn rates.

I do not believe that McNett uses blue dot for his commercial loads. I would expect he uses a commercially available powder that hobbyist hand loaders cannot get their hands on in small quantities without working with commercial loaders who might have stumbled on to what he has been using. I expect that his powder is going to be closer to AA#9 in burn speed, but that is simply speculation since I really don't know what he is using.

I just know it's not producing velocities that meet the claims on his boxes.

Unfortunately, since I put a bullet through the top of my chrony case today :crying: (table was too high for margin of error - will not make that mistake twice!), knocking into some internal parts - I will not be able to test any more until I either repair or replace the chrono (hoping the dealer has some parts available).

The idea of spring tension vs. velocity is worth testing anyway.

I am going to order a 24# spring and get the chrono replaced or repaired as soon as I am able so I can post my own findings.

I could also easily test the theory of 800x, which is slower than Blue dot. Before ripping a nice long hole through the case I was able to get through enough strings to know how to match the velocity of double tap's 200 gr. "controlled expansion" rounds (based on my small sample of 3 measured yesterday), so I suppose we could emulate the spring vs. velocity using that load...:supergrin:

Kegs
08-29-2010, 20:28
One more note:

I am using a 21# spring, not a 22#. I somehow got mixed up about that. Not sure how. The 21# springs aren't strong enough for any of the loads I run through this gun. :supergrin:

MalumProhibitum
08-31-2010, 08:12
UPDATE:


Someone recommended that changing the spring to a heavier will improve my chrono. I ordered the Wolff 24lb spring and guide rod combination.

I took the G20 to the range yesterday and shot the same ammo with the new spring. The conditions were pretty identical, both days in the low 90s temp wise and same humidity. These tests are a week apart so it is right on. Five shot string and posting the average.



Last week with stock barrel and spring: These are average

DT 135gr = 1463 ft/sec
DT 200gr XTP= 1089 ft/sec
DT 180 XTP = 1211 ft/sec


Yesterday with stock barrel and 24lb spring and guide rod: These are average

DT 135gr = 1582 ft/sec
DT 200gr XTP= 1214 ft/sec
DT 180 XTP = 1242 ft/sec


There is no question that 24lb spring helped. What is amazing is that it helped the most with the lightest bullet and in ascending order the heavier the bullet the less it improved with the heavier spring but all improved. I guess that there is so much more pressure/powder in the 135gr load that opens the breach face faster and longer changing the velocity.

Just wanted to post this because it somewhat gets DT off the hook. It is possible that at elevation (i am at seal level) those numbers can be another 50ft/sec faster which would be closer to their advertised data. Just copying to this page, so we do not lose track of what we were originally testing, doubting, or confirming. :cool:

Kegs
08-31-2010, 18:04
Just copying to this page, so we do not lose track of what we were originally testing, doubting, or confirming. :cool:Good idea. I sent the chrono in yesterday for repair and should have it back within a couple weeks or so. I ordered the 23# springs today from Wolff. I believe it is the max spring they had for the G29. Should work much better for my average load (nuke).

I still have a few rounds of that sissified double tap left, and I have my stock spring and stock barrel, which is obviously easy enough to change back. I will remain skeptical unless proven otherwise through my own results.

Stay tuned.

cowboywannabe
08-31-2010, 18:12
it seems Buffalo Bore is the only commercially recognized regular player for real 10mm loads. theyre the only ones that meet their box flap claims, or at least very close to it no matter who is shooting it and no matter if they have a stoch Glock or after market springs.....still wish they made a 165grainer~ that i could afford.

im leary of the 180grainer at 1350fps for personal defense against bad guys.....seems it would pass through the average bad guy with ease. maybe if this load were toned down to what the others claim to be....

Berto
08-31-2010, 19:24
Tim at BB actually mentions going to a heavier spring in the G20 to help reduce velocity extremes you will get with the stock ones.

PBRLite
09-01-2010, 08:45
Not sure if this has been covered or asked, and maybe it wouldn't make a lick of difference, but would shooting the gun in a machine rest like a "Ranson Rest" make any difference in velocity readings?

Along with a stronger recoil spring, and firing the gun 15 feet back from your chrono?

morphoffroad
09-02-2010, 06:22
One cause of lower measured velocity than DT's published velocity for full power loads may be that the G20 breach is unlocking prematurely. I had similar low results until I installed a stronger recoil spring.

Kegs
09-02-2010, 20:18
One cause of lower measured velocity than DT's published velocity for full power loads may be that the G20 breach is unlocking prematurely. I had similar low results until I installed a stronger recoil spring.

How much stronger is the spring you installed?

Kegs
09-02-2010, 20:22
im leary of the 180grainer at 1350fps for personal defense against bad guys.....seems it would pass through the average bad guy with ease. maybe if this load were toned down to what the others claim to be....

The main things I would be concerned about at a gun fight is #1 NOT GETTING SHOT, and #2 SHOOTING THE OTHER GUY BEFORE HE SHOOTS ME.

Get your priorities straight - and bring enough gun! :thumbsup:

Mike5560
09-08-2010, 01:01
and i thought that was common knowledge....the 17# spring being stock for the 10mm just like it is for the 9mm in the G17....spare me the heavier slide stuff folks....thats comparing ounces of slide weight to pounds of force of the stock vs. after-market springs...

its my feeling that Glock decided that the 17 pound spring along with the heavier slide of the G20 was plenty for the run of the mill watered down stuff that Rem. Fed. Win. Hornanday...etc puts out, and theyre right. but this combos is far from optimal for true 10mm powered loads.

I thought this was common knowledge as well. I basically impulse bought my G20 since I have .40/10mm dies and after about 5 minutes of online research. During that time, I found a page about the G20 and the reviewer noted extreme velocity spreads with the factory spring. Velocities were increased and more consistent with a heavier one. This has been talked about on the forum here as well.

gatorboy
09-08-2010, 16:39
One more note:

I am using a 21# spring, not a 22#. I somehow got mixed up about that. Not sure how. The 21# springs aren't strong enough for any of the loads I run through this gun. :supergrin:

The Wolff springs for the 29/30 are mostly odd numbered, mostly even for all other models with some exceptions.

sgtbones
09-10-2010, 22:12
A close friend of mine just shot 180gr (real Gold Dots) Swamp Fox AMMO
through a chronogaph. AVERAGE FPS WAS 1380 !!!!!!!!:cool:

Sheepdog Scout
09-11-2010, 03:19
A close friend of mine just shot 180gr (real Gold Dots) Swamp Fox AMMO
through a chronogaph. AVERAGE FPS WAS 1380 !!!!!!!!:cool:

Nice! I've got some SwampFox ammo coming my way. I'm excited to try them.

Billy10mm
09-12-2010, 21:49
I ordered a box of the 200gr XTP from Mike .... got a box with the 200gr label, but the bullets were 180gr GD's.

Mike won't be seeing any more of my money until I start reading "DT has turned themselves around" reviews.

MalumProhibitum
09-28-2010, 12:02
Good idea. I sent the chrono in yesterday for repair and should have it back within a couple weeks or so. I ordered the 23# springs today from Wolff. I believe it is the max spring they had for the G29. Should work much better for my average load (nuke).

I still have a few rounds of that sissified double tap left, and I have my stock spring and stock barrel, which is obviously easy enough to change back. I will remain skeptical unless proven otherwise through my own results.

Stay tuned. Ok, I am staying tuned.

Kegs
10-06-2010, 17:19
My conclusion is heavier recoil springs don't do SQUAT for increasing velocity.

Here's the skinny:

http://glocktalk.com/forums/showthread.php?p=16101316#post16101316

sgtbones
10-06-2010, 18:32
Swamp Fox Ammo boys!!!!!!!!!!

Kegs
10-06-2010, 19:16
Swamp Fox Ammo boys!!!!!!!!!!

Just saw his video. I edited this to say his ammo goes just about the same speed my 9.4gr. 800x load does. I have no idea how he can fire that in a stock Glock barrel without a great big smiley face on the case afterward.

I don't think I would attempt to fire that out of my stock G29.

1240 w/XTP out of a G20 stock barrel is going to be just about at the limits of the 37.k psi...

Finally...someone loading full power ammo!

One thing I would be a tad concerned about is how he can run one bullet through the chrono going 1250 and the next going 1200...That is a bit of a wide gap there.

Watch:

http://www.youtube.com/watch?v=sO9h-y0-p30

Sheepdog Scout
10-07-2010, 03:10
I figure it's probably like he said. He was having issues with his chrono. They don't always work correctly.

DanaT
10-09-2010, 09:57
Here is what I have measure out of a stock G20 with 165gr Golden Saber Double Tap loads.

This testing was done at 8500ft altitude.

Note that I had a stock recoil spring in the pistol when the data was taken so some of the deviation is likely due to spring.


All numbers in Ft/sec
1395 1385 1420 1368 1349
1362 1381 1382 1358

Mean. 1378ft/sec
Std Dev. 21.57
% RSD. 1.57%

I am not sure if those load were claimed at 1400ft/sec of 1425ft/sec.

I also take measurements at about 15ft to avoid muzzle blast interferences.

All in all, given the accuracy of my measuring equipment (Shooting Chrony) I would say the number are in the ballpark.

If someone in this forum actually has a chrono calibrated to a NIST standard, then maybe they can make the statement that thier numbers are more accurate. But lets be honest. The chronos people are using are cheap off the shelf units (even an Oehler is cheap off the shelf and is the best commercially available).

To get more accuracy, you need to purchase much more expensive equipment. For example, how many of you have calibrated masses to check your reloading scales against? How many of you use a balances (scale) that has precision to +/- 0.1mg (0.0015grains) and accuracy to +/- 0.2mg (0.003grains)? This is the difference between a consumer reloading scale ($100) and a lab grade scale ($5000). Yet I bet all the blow hards would say that some powder measurements I took with a NIST calibrated scale as described above were wrong because their $100 untraceable scales said something different.

Take the knowledge here with grain of salt.

-Dana

Kegs
10-10-2010, 09:06
Good points, Dana! Standards of tolerance aside, your measurements seem to support my suggestion that DT's numbers are pretty close leaning toward a tad optimistic.

OldCurlyWolf
10-10-2010, 09:07
Has anyone verified whether or not DT is using a pressure barrel for its velocity testing? A pressure barrel will consistently give higher velocities than a standard barrel.

:dunno:

Kegs
10-10-2010, 09:19
Has anyone verified whether or not DT is using a pressure barrel for its velocity testing? A pressure barrel will consistently give higher velocities than a standard barrel.

:dunno:

As far as I can tell he uses actual Glock pistols for velocity and related testing. For pressure testing, he has other equipment.


http://glocktalk.com/forums/showthread.php?t=336612

vaquero aleman
02-27-2012, 20:10
there are plenty of neophytes to bite on the 10mm loading and DT hype. they will take your place and you wont be missed....sadly.

Well, this "neophyte" switched from a G20 to a 21 and I geared up my rig for 45 Super so I guess now I will join the ranks of quiting DT, especially since they don't load 45 Super anyhoo.

arushus
02-27-2012, 21:09
A year and a half later....