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racking on 09-12-2012 16:08

Crimping ?
 
Do you have to crimp handgun reloades for best of grouping on paper at 15-30yds using 9mm G19, also has anyone heard of the consistent crimper at www.precisionaccuracycompany.com? If we do have to crimp will this crimper using lee factory crimp die be worth buying?

Zombie Steve 09-13-2012 12:07

Generally, you'll have to taper crimp to get it to function in a semi-auto, but don't think of it as crimping. Think of it as de-flaring the case. All you're trying to do is straighten it back out. Neck tension holds the bullet just fine.

Your normal seater die will be able to do this. You might want to do it in two steps, although both seating and crimping can be done at the same time. Just easier to take them one at a time.

Take your barrel out of your gun and drop a finished round in the chamber. Just crimp enough to get it to drop in flush with the barrel hood. It should fall out freely. That's all you need.

No need for the Lee fcd or any other fancy crimp dies. .

DoctaGlockta 09-13-2012 12:30

Quote:

Originally Posted by Zombie Steve (Post 19415414)
Generally, you'll have to taper crimp to get it to function in a semi-auto, but don't think of it as crimping. Think of it as de-flaring the case. All you're trying to do is straighten it back out. Neck tension holds the bullet just fine.

Your normal seater die will be able to do this. You might want to do it in two steps, although both seating and crimping can be done at the same time. Just easier to take them one at a time.

Take your barrel out of your gun and drop a finished round in the chamber. Just crimp enough to get it to drop in flush with the barrel hood. It should fall out freely. That's all you need.

No need for the Lee fcd or any other fancy crimp dies. .


SPIN2010 09-13-2012 12:35

Interesting ... why would you need to crimp straight case based calibers? I would think to just de-flare would be fine. I have never crimped a 9mm, 10mm/.40, or a .45ACP in over thirty years. Curious.

F106 Fan 09-13-2012 12:42

There are some fine target pistols in this world including the Colt Gold Cup and the S&W Model 52 (not even counting all the great .22s such as the S&W Model 41) but the Glock 19 isn't one of them. Nor was it intended to be!

One characteristic of a target pistol is a very crisp trigger break with no perceptible creep. The long-creep trigger of the Glock will never make the cut.

I have to be realistic about my shooting. My eyesight isn't much, my grip is questionable and the trigger on my G21SF just sucks. Still, I can keep the holes in an 8" circle at all practical distances. I can hold the 10 ring at 7 yards so I know the gun will shoot. I am the limiting factor in all my shooting. Not the firearms!

The Lee FCD isn't highly regarded around here for crimping ANY semiauto pistol cases although is sees some use for crimping revolver cases where the bullet has a cannelure such as .38, .44 MAG, .357 MAG and I'm using it to crimp .223 with a 55 gr FMJ. But any roll crimp die would work just as well and they have done so for many decades.

In terms of pistol loading, the FCD is supposed to solve a problem that shouldn't exist (improperly sized cases) and creates a problem that didn't exist (over crimping on straightwall pistol cases).

I prefer a taper crimp die on semiauto cases as a separate operation. Besides testing the loaded round in the chamber (remember, you can fit a bowling ball in a Glock chamber), you should make certain the casemouth of the top round in the magazine doesn't catch on the base of the case being ejected. I place a straightedge along the case to see that the taper has been totally removed.

Pull a few bullets after taper crimping and make sure the casemouth is not being embedded into the bullet. This is particularly important with plated bullets. The plating isn't very thick and cutting through it does nothing for accuracy.

As to measuring the torque applied during crimping, I wonder if the brass wall thickness and annealing make a difference. That is, given a few thousand random cases, all loaded in a batch, it would seem to me that even with consistent torque, some will be crimped more than others.

Of course we have the same problem with any other crimp technique because, unless case length is absolutely uniform, the crimp depth will vary.

For precision rifle, there is an arbor press for bullet seating that measures neck tension. But precision rifle is a whole different thing than loading dumpster quantities of pistol ammo.

Richard

fredj338 09-13-2012 13:08

Quote:

Originally Posted by SPIN2010 (Post 19415495)
Interesting ... why would you need to crimp straight case based calibers? I would think to just de-flare would be fine. I have never crimped a 9mm, 10mm/.40, or a .45ACP in over thirty years. Curious.

If you are using the taper crimp in the seating die to remove the flare, then you are mildly taper crimping. So yes, always crimp your semiauto ammo ofr proper functioning. Leaving the flare or bell, even only 0.001" can cause feeding issues.
There have been reams written about the uslessness of the LFCD. A poor solution to just about any problem your ammo may have. If you need a LFCD to get your ammo to work, then you need a reloading class not a LFCD.

Colorado4Wheel 09-13-2012 13:54

Taper crimping IS deflaring. Simple as that. Only time your are actually bending the case inward is when you have the bullet seated short enough to bend it inward with out denting the bullet. Its pretty clear if you look at the Lyman reloading manual.

fredj338 09-13-2012 18:23

Quote:

Originally Posted by Colorado4Wheel (Post 19415764)
Taper crimping IS deflaring. Simple as that. Only time your are actually bending the case inward is when you have the bullet seated short enough to bend it inward with out denting the bullet. Its pretty clear if you look at the Lyman reloading manual.

Yes Steve, but it's not called a taper flare but a taper crimp. Come on guys, you are getting way off into the weeds.:upeyes:

HAMMERHEAD 09-13-2012 18:46

with minimum flare/expansion of the case mouth, all you need to do is bump the case mouth with a taper crimp die to straighten them out. Redding, RCBS, heck, even Lee make good crimp dies.
No need for the FCD or some fancy crimp die.
Sorting cases, ensuring consistent powder charges, straight line bullet seating will all have more affect on accuracy than the brand of crimp die you use.

Colorado4Wheel 09-13-2012 18:53

Quote:

Originally Posted by fredj338 (Post 19416760)
Yes Steve, but it's not called a taper flare but a taper crimp. Come on guys, you are getting way off into the weeds.:upeyes:

A roll crimp die would remove the flare just as well. Just saying. It's irrelevant if all you do is use minimal flare and the declare.

SPIN2010 09-13-2012 19:14

Just an example.

Quote: Throughout the rest of this discussion, bear in mind the fact that not all cartridges will require a crimp of any kind. For those cartridges which can be loaded without resorting to a crimp, we recommend omitting this step altogether.

http://exteriorballistics.com/reloadbasics/crimp.cfm


... and to be fair. The article covers taking out the flare on a straight case as crimping. :dunno:

sciolist 09-13-2012 20:06

I taper crimp all my 9mm to 0.375.

dhgeyer 09-14-2012 09:55

Since no one else has mentioned it, I will. Too much crimp can be dangerous. Remember, the 9mm, 40, 45, and other straight walled rimless pistol cases headspace on the case mouth running into the step at the end of the chamber. If a case is crimped too much, it could wedge itself a bit past that step. This would drastically raise pressure, as the case would not release the bullet properly.

This degree of overcrimping would be difficult with standard dies for the caliber. But it is possible if one gets overzealous. When setting up the seating/taper crimping die, look to see if the case mouth is getting deformed or shaved. If it is, that's way too much crimp. And NEVER NEVER roll crimp a straight walled rimless pistol cartridge for a semi-auto pistol. Roll crimping is for revolvers with rimmed cases, or rifle cartridges. This would be hard to do anyway unless one was using bullets with a groove or cannelure. Cast bullets have them. One could overcrimp a soft lead bullet, too, to the point of being dangerous.

SARDG 09-14-2012 10:35

Quote:

Originally Posted by sciolist (Post 19417133)
I taper crimp all my 9mm to 0.375.

That seems like a lot as the SAAMI case mouth measurement is .380.

SARDG 09-14-2012 13:44

Quote:

Originally Posted by SARDG (Post 19418801)
That seems like a lot as the SAAMI case mouth measurement is .380.

I've been measuring factory and some of my reloads with different bullets... Is that SAAMI figure "nominal"? "maximum"? There is no time in the reloading process where .380 is achieved with my setup (except the temporary flare of course).

F106 Fan 09-14-2012 14:02

The .3800" dimension is a 'reference'. There is no tolerance specified other than note about Body Diameter - 0.007".

The .3800" also must be a MAX number because the chamber is spec'd at 0.3810" and there must be some clearance or the slightest puff of smoke will keep a round from chambering.

The .3810" dimension is also a 'reference'. If it has a tolerance, it is +0.004".

Notice that the 0.3800" and 0.3810" are specified to the nearest ten thousandth of an inch. The spec if very serious about these numbers to have spec'd them to 4 decimal places.

Richard

fredj338 09-14-2012 18:09

Quote:

Originally Posted by Colorado4Wheel (Post 19416874)
A roll crimp die would remove the flare just as well. Just saying. It's irrelevant if all you do is use minimal flare and the declare.

Correct & I have done that. Still, it is correct to call it crimping because you are using a taper crimp die. Semantics maybe, but is what it is.:dunno: FWIW, I don'tthink I have ecer measured case mouth crimp. If you can see a crimp w/ a taper crimp, it's too much.

Colorado4Wheel 09-14-2012 18:16

I just want people to understand that you don't actually bend the case inward.

unclebob 09-14-2012 19:21

Quote:

Originally Posted by F106 Fan (Post 19419504)
The .3800" dimension is a 'reference'. There is no tolerance specified other than note about Body Diameter - 0.007".

The .3800" also must be a MAX number because the chamber is spec'd at 0.3810" and there must be some clearance or the slightest puff of smoke will keep a round from chambering.

The .3810" dimension is also a 'reference'. If it has a tolerance, it is +0.004".

Notice that the 0.3800" and 0.3810" are specified to the nearest ten thousandth of an inch. The spec if very serious about these numbers to have spec'd them to 4 decimal places.

Richard

And if you over crimp you start sizing the bullet.

fredj338 09-14-2012 22:45

Quote:

Originally Posted by Colorado4Wheel (Post 19420372)
I just want people to understand that you don't actually bend the case inward.

Very true, why I always tell noobs to pull a bullet & see how it looks. You can also over crimp w/ a roll crimp, but it's harder to do.:wavey:

Gpruitt54 09-17-2012 21:09

I just returned from the range after trying out my first reloading 9mm rounds. I've been reloading .40S&W rounds for a month. I've loaded and fired about 300 .40S&W rounds with no issues at all. However my 9mm reloads had lots of feeding issues. Out of 200 rounds, about 10 rounds jammed while the rounds were moving up the feed ramp. I am using a factory crimp (Lee 4 die set), but apparently I am not putting enough crimp on the rounds.

So, how much crimp is enough; and how much crimp is too much; and how do Itell when enough is enough? I have to assume that I have not enough crimp on my 9mm rounds. But I need some confirmation. During my range visit, the accuracy was very good; nice tight groups, though slightly to the left of aimpoint. Factory rounds are dead-on true to aimpoint.

I am using 115gn 9mm FMJ bullets form Precision Delta. My brass is once fired brass that has been tumbled clean to a high shine.

My weapon is a Glock19.

F106 Fan 09-17-2012 21:55

This entire thread has been about crimping straightwall pistol cartridges.

All you want to do is close up the case mouth. You don't want to crimp so much that you mark the bullet. The casemouth should be about 0.0001" smaller in diameter than the diameter of the cartridge about 0.030" away. In other words, put a straightedge along the bullet and you should not see daylight anywhere along the bullet portion of the cartridge.

The other thing mentioned in this thread is the the FCD is NOT the way to do it. Use the thing on a fishing line and after you cast, cut the string.

Buy a legitimate Taper Crimp Die
http://www.midwayusa.com/find?userSe...aper+crimp+die++

See post #5 in this thread for more about the FCD

Some bullet profiles are harder to feed than others. Sometimes excessive OAL make feeding more difficult.

If you are using plated bullets, make sure your crimp doesn't break through the plating. You have a little more latitude to overcrimp on lead or jacketed bullets but you still shouldn't leave much of a mark. It is important that the round headspace on the casemouth and this won't happen if you bury it in the bullet.

Do you have a case gauge? If not, get one.

Take the barrel out of your gun and use the chamber as a gauge. Drop a loaded round in the chamber and spin it. The only part that should drag is the leading edge of the case mouth. You can put Dykem Blue on the cartridge to see where it rubs the chamber.


You can also use a Sharpie.

Richard

Jager247 09-18-2012 03:07

You will need to remove the bell that the powder/expander die put in. You will either need to use the crimp function of the seater die or FCD to do that. I like to use the FCD because I like to use the post sizing ring as a case gage. If the round doesn't get post sized it should be within spec and function in your gun. If it does get post sized then I set it to the side and inspect it or pull it apart and reuse the components.

shotgunred 09-18-2012 06:11

Quote:

Originally Posted by Gpruitt54 (Post 19430768)
[FONT=Times New Roman][SIZE=3]

So, how much crimp is enough; and how much crimp is too much; and how do Itell when enough is enough? I have to assume that I have not enough crimp on my9mm rounds. But I need some confirmation. During my range visit, the accuracywas very good; nice tight groups, though slightly to the left of aimpoint.Factory rounds are dead-on true to aimpoint.


You are trying to straighten the case wall with out pushing it in. So it should feel straight with your finger. It should hold the bullet so that you can not move the bullet in the case by pushing on it. But no tight that if you pull it there is a mark on the bullet when you pull it..

Gpruitt54 09-18-2012 11:02

Quote:

Originally Posted by shotgunred (Post 19431407)
You are trying to straighten the case wall with out pushing it in. So it should feel straight with your finger. It should hold the bullet so that you can not move the bullet in the case by pushing on it. But no tight that if you pull it there is a mark on the bullet when you pull it..

Great! I'll go back and reset the factory crimp die to a better setting. I started with using a factory round as a starting setting for the factory crimp die.


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