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BMiracletx
08-08-2012, 07:29
Hey guys,

I have been reading this forum for awhile, but decided to finally stop lurking and join.

Here is my problem. I have a 3rd Gen 20SF. Been running into problems with FTFs. I have a Lone Wolf barrel in it, however the same type FTF happens with the stock barrel as well.

The load is 200 XTP over a heavy dose of Longshot. Not sure what the specific grains is since I am at work and don't have my log book. Either way, it is chrono'ing right at 1200 fps out of the stock length Lone Wolf barrel.

THe FTFs are a "slide over base" style. The slide is not picking up the case head and is jamming it up into the barrel hood. I have tried varying the OAL from 1.25-1.26", and tried spring weights from tghe stock 17# through 24#, and the thing just won't run reliably. Even witht he 24# spring it still launches the brass pretty good. The load works good on penned/trapped wild pigs, but I don't trust it reliably enough to carry when we are ground stalking the piggies.

So, any thoughts? By the way, the thing will run 155 XTPs over 12 grs of BlueDot all day long without any problems. Seems tlike it just doesn't like the 200 XTP and Longshot. (Haven't tried the 200 with Bluedot yet... would changing the powder make a difference?)

Edit: oh yeah... not a magazine issue because I have tried many different mags.

_The_Shadow
08-08-2012, 11:33
Well it does seem like the slide is running fairly fast with all the various weights of springs, given the ejected brass distance. I doubt the 200 nose will be the issue if the 155's run well.

Therefore I was thinking that the magazine springs may not be popping the rounds up fast enough to ride to the chamber. There are extra power springs for the magazines.

You may want to try a different magazine.Edit: oh yeah... not a magazine issue because I have tried many different mags.
Magazine lips could be out of alignment.
Have you disassymbled the magazine and cleaned inside, check for damage to the follower.

You can try to load to less entergetic potential also just to test the outcome.

BMiracletx
08-08-2012, 11:44
Well, like I said, I have tried the 3 mags that came with the gun, bought another one, and borrowed mags from the range I shoot at and it seems like they all do it.

I thought about the mag springs and already ordered the Wolff extra power mag springs to try and pop those suckers back up quicker. I doubt the mag lips are out of alignement since I have tried several mags from different places (all factory OEM).

I am out of ideas if the stronger mag springs don't work. Maybe I will just have to "de-tune" my 10mm! Don't want to do that though.....

Taterhead
08-09-2012, 09:32
Here is another angle to look at. For me, the felt recoil of the 200 grain load that you describe has far more of a recoil impulse than the 155 grain load that you describe. The nose profile for both are similar so we can eliminate that as a source of difference.

I have observed with the slide off that a magazine can be twisted, turned, and pushed fore-and-aft in a way that shifts the cartridge alignment materially. I can imagine that a grip that put enough torque on the mag base could give enough twist to pull the cartridge just out of alignment. A high impulse recoil would exacerbate this phenomenon.

You might look at the grip to see if twist is being imparted on the mag with the support hand. You might try to shoot them strong hand only to know for sure.

Just a thought, since the round is clearly not being collected by the slide return. A misaligned mag or cartridge could cause that.

Good luck and welcome to the forum.

BMiracletx
08-09-2012, 09:49
Here is another angle to look at. For me, the felt recoil of the 200 grain load that you describe has far more of a recoil impulse than the 155 grain load that you describe. The nose profile for both are similar so we can eliminate that as a source of difference.

I have observed with the slide off that a magazine can be twisted, turned, and pushed fore-and-aft in a way that shifts the cartridge alignment materially. I can imagine that a grip that put enough torque on the mag base could give enough twist to pull the cartridge just out of alignment. A high impulse recoil would exacerbate this phenomenon.

You might look at the grip to see if twist is being imparted on the mag with the support hand. You might try to shoot them strong hand only to know for sure.

Just a thought, since the round is clearly not being collected by the slide return. A misaligned mag or cartridge could cause that.

Good luck and welcome to the forum.

That all makes sense, however I don't think this is the case for me. I have medium sized hands and use a high/forward grip with my support hand to provide more compression/grip strength. Neither of my hand are ever in contact with the magazine base when holding my 20sf. I have tried both strong hand only and weak hand and find that there is really no difference in the frequency. It will hang up with the same frequency with a 2-hand grip or weakside single hand.

I am at a loss here. I have tried everything that you guys have come up with (except don't have extra power mag springs yet). I will try the extra power mag springs, as well as shortening OAL to 1.245 and see if that helps.

robert91922
08-09-2012, 12:15
I had the same problem a month ago. See this thread - especially pictures attached:
http://www.glocktalk.com/forums/showthread.php?t=1430147
Solved it w. Arredondo mag springs (Wolf +10% springs) but without extension added.
It started happening with really hot loads 212 gr HC @ 1230fps and got worse at higher summer temperature.
Before you get such mag springs try to detach tactical light if you got one on the gun. It solved my FTF problems at approx. 70% but since I bought G20 for hunting trips I decided to leave it attached and as said bought stronger mag springs.

Beside that, stiffer recoil spring would make problem worse cause slide gets a bit faster or even moves forward before gets all over to the rear end.

Now I carry 1 round less in mag than before cause these new springs are really hard and don't need full mag for hunting purposes.

BMiracletx
08-09-2012, 12:39
I had the same problem a month ago. See this thread - especially pictures attached:
http://www.glocktalk.com/forums/showthread.php?t=1430147
Solved it w. Arredondo mag springs (Wolf +10% springs) but without extension added.
It started happening with really hot loads 212 gr HC @ 1230fps and got worse at higher summer temperature.
Before you get such mag springs try to detach tactical light if you got one on the gun. It solved my FTF problems at approx. 70% but since I bought G20 for hunting trips I decided to leave it attached and as said bought stronger mag springs.

Beside that, stiffer recoil spring would make problem worse cause slide gets a bit faster or even moves forward before gets all over to the rear end.

Now I carry 1 round less in mag than before cause these new springs are really hard and don't need full mag for hunting purposes.

YEP! That is excactly what mine is doing! So hopefully when these new mag springs come in next week that will solve the problem. That should get that round popped up faster, and hopefully then play with the recoil springs to find the best weight.

As for the light, that is not a problem here since I don't have a light attached to this gun.

Hopefully combination of heavier mag spring, recoil spring,and maybe a slight reduction in the load will help this thing run reliably. But, like you said, until then I will keep my Ruger Blackhawk in 45 colt loaded with some good loads until this 20sf is sorted out.

robert91922
08-09-2012, 13:24
I agree with you about 45 L.C. Ruger Blackhawk. It's a good and reliable handgun if you are good enough in SA shooting. And if you got some hot modern reloads in wheel you are not underpowered, more opposite.
http://www.chuckhawks.com/high-pressure45.htm

I carried my 44 magnum Taurus in woods until solved that FTF problem for sure. It's a bit heavier than Glock 20 but I didn't care a lot :supergrin:

BMiracletx
08-09-2012, 14:05
I agree with you about 45 L.C. Ruger Blackhawk. It's a good and reliable handgun if you are good enough in SA shooting. And if you got some hot modern reloads in wheel you are not underpowered, more opposite.
http://www.chuckhawks.com/high-pressure45.htm

I carried my 44 magnum Taurus in woods until solved that FTF problem for sure. It's a bit heavier than Glock 20 but I didn't care a lot :supergrin:

Oh yeah... I know all about those. My standard carry load in the woods is a 255 LSWC over 13 grs of HS-6 which is a John Linebaugh recommended load. It runs out of my Blackhawk at 1050fps (exactly what he has posted out of his own Blackhawks). It is not the hottest load I have shot through it, but that load will still penetrate all the way through a 3-400 pound hog. If you haven't seen John Linebaughs site, check this out. He has done a lot of testing with Blackhawks. At the end of his writing is his "pet loads". I have shot them all in my Blackhawk and they all shoot good.

http://www.customsixguns.com/writings/dissolving_the_myth.htm

orangeride
08-11-2012, 09:20
I've been running +10% wolf and glock 11 coil springs in three of my 20sf mags with no problems at all. Also what primer are you using? I use a stiff load of Longshot with a 200 gr bt hc for 1230fps and standard fed primers. Swampfox once suggested that standard primers on really hot loads might smooth out the recoil impulse and help feeding. Lastly, are you shooting new brass? Or brass that's been fired many times? All my reloads go through a lee buldge buster when there done. I started getting major feeding issues on my 3rd and 4th loadings of brass. The BB fixed all that. I have a LW 5.2" barrel but almost never use it. The stock one handles the HC better and is totally reliable but does leave a med. buldge on hot loads.

BMiracletx
08-11-2012, 09:54
I've been running +10% wolf and glock 11 coil springs in three of my 20sf mags with no problems at all. Also what primer are you using? I use a stiff load of Longshot with a 200 gr bt hc for 1230fps and standard fed primers. Swampfox once suggested that standard primers on really hot loads might smooth out the recoil impulse and help feeding. Lastly, are you shooting new brass? Or brass that's been fired many times? All my reloads go through a lee buldge buster when there done. I started getting major feeding issues on my 3rd and 4th loadings of brass. The BB fixed all that. I have a LW 5.2" barrel but almost never use it. The stock one handles the HC better and is totally reliable but does leave a med. buldge on hot loads.

I am running the Wincehster Large pistol primer. Not using magnm primers. I load heavy loads with new Starline brass, then they all go through a redding pass through sizer. I have not had any problems with bulging on the hot loads since all are fired through a Lone Wolf barrel, but I still run the heavy laods through the full length sizer. I will then load medium loads through the once fired brass, but after that, the twice fired brass goes into the "plinking load" box. For plinkers I use 6grs of 231 powder under a plated 155 bullet which gets about 1020 fps... light but accurate. So to answer your question, it is not due to oversized case heads. All my loads drop nicely into the chamber. They just hang up getting to the chamber. I think the answer will be the new mag springs.

orangeride
08-11-2012, 10:15
One other thing I thought of that was causing me problems when I worked up my HC load was the OAL and the wide meplet. When I first worked up the load it was in five shot strings that I crononed each load. I seated at 1.26". They always fit fine in the mag and feed good. Well, once I finalled my load and loaded up all my bullets I started getting tons of FTFd. Come to find out, at 1.26" OAL the first 5-6 fit fine in the mag but as I loaded more the inside of the mag (all six of mine) got tighter and the wide meplet was dragging slowing down the mag. I re-did my load at 1.242" and everything works great now. I've never shot the xtp's so I'm not positive what the nose profile looks like, but it's worth stuffing the mag and looking down inside. Any small amount of drag could cause an issue. Also the win. Primer is still considered pretty hot. You might try the standard cci or fed. But I don't think that's the real issue. Lastly, you might go back to the stock barrel and rsa till you get the reliability. Then start messing with things.

BMiracletx
08-11-2012, 10:47
One other thing I thought of that was causing me problems when I worked up my HC load was the OAL and the wide meplet. When I first worked up the load it was in five shot strings that I crononed each load. I seated at 1.26". They always fit fine in the mag and feed good. Well, once I finalled my load and loaded up all my bullets I started getting tons of FTFd. Come to find out, at 1.26" OAL the first 5-6 fit fine in the mag but as I loaded more the inside of the mag (all six of mine) got tighter and the wide meplet was dragging slowing down the mag. I re-did my load at 1.242" and everything works great now. I've never shot the xtp's so I'm not positive what the nose profile looks like, but it's worth stuffing the mag and looking down inside. Any small amount of drag could cause an issue. Also the win. Primer is still considered pretty hot. You might try the standard cci or fed. But I don't think that's the real issue. Lastly, you might go back to the stock barrel and rsa till you get the reliability. Then start messing with things.

The XTPs do not have a wide meplat. They do not drag the magazine body even at 1.26' OAL.

Any Cal.
08-11-2012, 23:59
Here is another angle to look at. For me, the felt recoil of the 200 grain load that you describe has far more of a recoil impulse than the 155 grain load that you describe. The nose profile for both are similar so we can eliminate that as a source of difference.

I have observed with the slide off that a magazine can be twisted, turned, and pushed fore-and-aft in a way that shifts the cartridge alignment materially. I can imagine that a grip that put enough torque on the mag base could give enough twist to pull the cartridge just out of alignment. A high impulse recoil would exacerbate this phenomenon.

You might look at the grip to see if twist is being imparted on the mag with the support hand. You might try to shoot them strong hand only to know for sure.

Just a thought, since the round is clearly not being collected by the slide return. A misaligned mag or cartridge could cause that.

Good luck and welcome to the forum.

I had not seen this before you mentioned it, but think it may be the cause of a random FTF I started getting recently. I just epoxied strips of some material on the mag to see if it fixes the problem. Thanks for the heads-up!:horsey:

BMiracletx
12-13-2012, 08:09
Well, guys, despite all of these suggestions I could never get that 20SF to run right... so it was liquidated from my collection a few months back. I still have that 10mm bug though... so today I am picking up a new 20SF. I really hope this one runs better. Perhaps I had just gotten a lemon. Fingers crossed!