Auto Pistol Rounds: to crimp or not to crimp

[GLOOB]

I am using the Lee 4 die sets. I have read over and over how great the FCD is for auto pistol rounds. I think the saying goes "Once you use an FCD, you'll never go back to seating/crimping in one step." Then in the next post, I read that taper crimping an auto round is only to ensure proper feeding. That if the cartridge chambers, it's unnecessary. So which is it? (BTW, I tried to pull a 9mm bullet that was completely uncrimped, and gave up after 5 good whacks, so I'm starting to lean towards the latter view, myself.)

So here's the issue. When I run my 9mm and .45 cartridges through the FCD per instructions, the diameter of the mouth doesn't change on 95% of the rounds. They are in spec, already. Only the occasional longer brass with a larger bell seems to get any benefit. So I tried using the seating die to crimp, and the ammo looks the same to me. So I guess I'm just asking why the big hoopla over FCD's, particularly with semi-auto rounds?

 

[cfullgraf]

I have been taper crimping my semi auto rounds since I started reloading in 1980. In fact, many of my taper crimp dies are Lee as Lee taper crimp dies were the most readily available as well as being value priced.

Some of Lee's equipment is excellent, value priced reloading tools but some of them are solutions looking for problems. By the time the FCD dies came on the market, I figured it fit the latter category so I never felt the need to buy one. Still don't.

But lots of folks like them.

I find a taper crimp die does a nice job of removing the mouth belling after the bullet is seated. I crimp in a separate step from bullet seating.

 

[Steve C]

I taper crimp my semi auto rounds enough to prevent bullet setback during feeding and subsequent extraction when clearing the weapon.

 

[GLOOB]

Hmm. Cfullgraf, maybe I'm not 100% understanding this reloading stuff. AFAIK, a Lee FCD for auto pistol is a taper crimp die. So I guess I was wondering why bother doing a taper crimp in a separate step, considering that it's such a trivial amount of crimp that 95% of my cartridges aren't even changed by it? What's so much better about doing it in a separate step? For that matter, if you wanted to do it in a separate step, you still wouldn't need the FCD die, you could just readjust the seating die? (WEll, at least on a single stage press).

 

[sourdough44]

I usually adjust the seating die high enough so it does not crimp. I use the FCD just a bit. It starts back when we 'belled' just enough to get the bullet in. At least make sure any belling is out & the bullet is held securely You can measure the mouth for proper size when done. Take your barrel out & make sure the rounds go in place easily & are held in position.

 

[Walkalong]

So I guess I was wondering why bother doing a taper crimp in a separate step, considering that it's such a trivial amount of crimp that 95% of my cartridges aren't even changed by it? What's so much better about doing it in a separate step? For that matter, if you wanted to do it in a separate step, you still wouldn't need the FCD die, you could just readjust the seating die?

Exactly. No amount of crimp will make up for poor neck tension. neck tension keeps the bullet from getting pushed in deeper. The crimp is just to remove the bell and or a hair more. It is easier for some folks to set up the seating and crimping in separate steps, but like you posted, there is so little crimp going on in a auto pistol round it is not necessary to crimp in a second step. Some crimp applications in revolver rounds work better in two steps, and some even have to be done in two steps, but for auto pistol rounds it is not needed.

The big selling point of the FCD for pistols is the carbide ring that ensures the round fitting your chamber, even if it has to squash it to do so. Kind of a fail safe, but one that (IMHO) is not needed, and can damage a finely crafted round.

Any way, lots of folks like them, and they crimp as well as any other crimper. After all, a taper crimp is a taper crimp when we are talking about the small amount used in a straight walled auto caliber.

 

[cfullgraf]

GLOOB, I taper crimp in a separate step because when I got into reloading, dies that taper crimp were only available as a die separate from the seated die. So, to taper crimp, you adjusted the standard seated die so as to not crimp, then run the cases through the taper crimp die. Since I still use the same old dies, I still taper crimp in a separate operation.

Over the years, I found some over all cartridge length inconsistencies with roll crimped revolver rounds and I now also crimp revolver rounds in a separate operation. I believe some interferences occur during the last stages of seating the bullet when crimping at the same time that effects the bullet seating depth.

Last year I finally purchased a progressive press primarily for hand gun ammunition. I still load ammunition in separate steps, resize, clean, then reload. During the resizing step, I resize a case and expand the mouth of another case at the same time. Ditto when seating the bullets. Taper crimp operation happens with no additional case handling during the same pull of the handle.

The body sizing feature of the Lee pistol factor crimp die is unnecessary as Walkalong said. I have never had a cartridge not chamber because it was not sized correctly. In my opinion, a solution looking for a problem.

As taper crimp die, the FCD probably performs well and if you fell better using it, then by all means use it. Your reloads will be better and you will shoot better if you have more confidence in your reloads.

Finally, I enjoy reloading as a hobby, itself. I am also a gadget guy and have lots of special reloading tools cluttering my reloading room. Some good, some not so good, but all purchased with the idea it would make my ammunition better, or more efficiently. It is all part of my reloading enjoyment.

 

[MrOldLude]

If you have good neck tension, crimping really isn't needed. But I just like that extra bit of piece of mind when running off my 9mm rounds.

 

[Jim Watson]

not needed, and can damage a finely crafted round.

True, but not all rounds are finely crafted.
If you are loading bulk commercial cast bullets in mixed range pickup brass, lumps and bulges are unfortunately common to the point that some loaded rounds will not gauge. The CFC die will iron them out.

The moly coated lead bullets I am using now do not fit that category and a light taper crimp is all I do.

 

[stork]

My comments are from one who has never used a Lee FCD, but I have done very extensive testing with Match grade Bullseye guns on my Ransom Rest.

When I started loading 45 ACP I used a set of RCBS dies that only roll crimped. I didn't know things like taper crimp dies even existed. I had extensive experience with revolver and rifle reloading but none with semi auto pistol cartridges. I had a lot of jams with my rounds being oversized for the chamber until a fellow Bullseye shooter asked what I was taper crimping my round to. My 'HUH' look told him all he needed to know and he proceeded to tell me to buy a taper crimp die and play with it. At first I TC'd to .470 and the feeding problems were virtually eliminated.

Then I got my first Kart barrel fitted to my wad gun and about the same time acquired a Ransom Rest. Then the real testing began. What I found is that my new barrel loved to be crimped to .465 for the 50 yd load (4.4 WST and H&G 68). When I had my hardball gun built I did the same testing, Kart barrel again, same gunsmith, same chambering reamer, but this one liked to be crimped to .469-.470. For a time I kept loading both loads because I was shooting the ball gun a lot in order to get my distinguished badge. Since I got that I don't shoot the ball gun much and now just load for the wad gun. In 2007 I rebarreled my wad gun with a new Kart and this barrel likes a .468. I must also add I no longer water drop my cast bullets, so they wind up a little softer than before. A very general rule is the softer the bullet/ the lighter the crimp- the harder the bullet/ the harder the crimp. If I shot commercial swaged bullets I would only crimp to .470...I think.

But I digress, the point that I'm trying to make is the amount of taper can make a really big difference on how well your pistol will shoot. The tighter the crimp the longer the bullet will be held in the case and the powder charge is burned more completely and, in some cases, better accuracy will result.

One of the finest bullseye 1911 gunsmiths by the name of John Giles always cut his chambers to give best results with a .463 crimp and the H&G 130 bullet. He has since passed on but his son posts with some regularity on the Bullseye List and has shared that his dad never sent out the best of the test targets his pistols shot. There were stacks of targets with 10 shot groups under an inch at 50 yards. While I have tested crimping to .463 I didn't get any better accuracy than .465 so opted to stay there to avoid over-working my brass.

FWIW

 

[Walkalong]

If you are loading bulk commercial cast bullets in mixed range pickup brass, lumps and bulges are unfortunately common to the point that some loaded rounds will not gauge. The CFC die will iron them out.

Jim is absolutely right, and for those not wanted to gauge hundreds of rounds made in that manner, the FCD is the answer.

 

[rcmodel]

Taper crimp doesn't hold the bullet in the case, unless you are over-crimping to the point of squeezing the case mouth into the bullet and damaging it.
Proper neck tension is what prevents bullet set-back during feeding.

As an aside, I have measured all manner of GI issue .45 ACP ball & National Match ammo. Then pulled the bullets to inspect them.

They will range from .469" to .471", depending on the neck thickness of the brass in question.

That amount of crimp leaves the case mouth just barely touching the bullet jacket, without actually scoring into it and leaving a crimp ring on the bullet.

rc

 

[rfwobbly]

Gloob -
The on-going discussion of the Lee FCD seems to me to be predicated on what type bullet you use as to whether it "helps" or not. The most ardent admirers seem to be lead bullet users. Lead bullets can sometimes vary widely in diameter and shape even when taken from the same box, and so I can understand the need of using a final "cartridge uniforming die".

The folks that seems to feel the Lee FCD is an extra, unnecessary step are those that stick to plated and jacketed bullets, which are usually hold much tighter dimensional tolerances. So the answer to your question may lie more with what bullet you're shooting than anything else.

 

[Walkalong]

I loaded thousands of lead bullets (both commercial and home cast) in 9MM, .38 Spl, .44 Spl, and .45 ACP for years before the FCD was invented. Never a chambering problem, never a leading problem. How in the world did I manage.

 

[Bovice]

Why do so many people seem to resent the existence of the factory crimp die? What's the big deal anyway?

In regards to crimping:

Once I loaded a batch of .40s that were not crimped. 4 or so rounds out of the 100 would hang up just outside of the chamber. It was easy enough to fix, just pulling back on the slide a little and letting it go made the round go right in. But it was the slight bell that the expander was leaving, giving it just an ever-so-slight edge to snag. When I run them through my FCD, that gets fixed. It just makes life so easy. I think i got mine for about $30. I have one for 9mm as well.

One last thing: accuracy is crap without a crimp.

 

[GLOOB]

Well, I believe this thread has completely answered my questions.

I am using plated bullets. I don't hunt or shoot from a bench rest. So I will be leaving out the FCD. But I will be setting my seating die to remove any bell on the occasional brass with too much flare. So far it seems to be as simple as screwing the die all the way to the shellholder and backing it out 2 turns instead of 3. My .45 acp comes out with mouth dimensions somewhere between .470" and .471" with no bell.

Thanks to all for sharing your wisdom and experience.

Stork:

When I started loading 45 ACP I used a set of RCBS dies that only roll crimped.

Are you sure those were .45 ACP dies? Sounds like you were using .45 revolver dies. I don't think RCBS would put a roll crimp on an auto pistol die. My Lee auto pistol seating dies do a taper crimp. And my Lee auto pistol FCD's also do a taper crimp. My Lee .38 dies do a nice roll crimp, and I'll be sticking with the FCD for crimping those, for now.

When I run them through my FCD, that gets fixed. It just makes life so easy.

Yeah, bovice. But you can set your seating die to remove that little flare, too. That makes life even easier, if all you have is a single stage press. If you have uniform brass, you can even set your expander die for the minimum flare, and you don't need to crimp, at all. So I understand the concept of crimping in a separate step for a roll crimp, because you don't want to damage the bullet and you want consistent seating depth. And I now understand the desire for an FCD to ensure lead bullets chamber. But I still don't understand the need for either with a plated auto pistol round, unless it improves your accuracy.

 

[Walkalong]

But it was the slight bell that the expander was leaving, giving it just an ever-so-slight edge to snag. When I run them through my FCD, that gets fixed.

As would crimping them with any taper crimp die.

accuracy is crap without a crimp

Not necessarily.


Resent the FCD? Nope, just sometimes get tired of hearing the "miracles" it performs.

Well, I believe this thread has completely answered my questions.

I agree. Sounds like you are well on your way.

Some .45 ACP crimp pics.
.

 

[PO2Hammer]

Once I loaded a batch of .40s that were not crimped. 4 or so rounds out of the 100 would hang up just outside of the chamber. It was easy enough to fix, just pulling back on the slide a little and letting it go made the round go right in. But it was the slight bell that the expander was leaving, giving it just an ever-so-slight edge to snag. When I run them through my FCD, that gets fixed.

One last thing: accuracy is crap without a crimp.

If you're having problems without a crimp, you're probably over flaring/expanding and are creating bulges and have lost bullet tension. Reduce your flare, and you won't need to compensate with over crimping.
My most accurate 9mm and .38 Super rounds were rounds that were not crimped at all, and I didn't flare the cases either, just resize/reprime/charge and seat the bullets with a straight line seating die.

Let the bullet expand the case whenever possible.

In .45acp I started with the Lee FCD set, then bought a Redding competition seater and there was no more need for the FCD. I only kiss the case mouth with the expander to remove dents ( .001"-.003" flare) and seat and just touch the case mouth with the crimper to make sure they are no burrs or nicks to prevent smooth feeding, no measurable crimp.

10mm I crimp about .003".

I haven't used my FCD dies in over a year and my ammo has never been better.

 

[cfullgraf]

GLOOB,

My 1980 vintage 45 ACP, yes 45 Auto Colt Pistol as in those cartridges used in the M1911 pistol, dies have a roll crimp cut in them. Auto pistol cartridge dies with taper crimp is a relatively new thing.

In those days, books, manuals, authors and other experts always cautioned about crimping the auto pistol cases too much with these dies as the roll crimp would cause the case to seat too deep in the chamber.

In 1980, taper crimp dies were available as special order items for the most part and not widely used.

Besides, a 45 ACP case would not even reach the crimp ring in a 45 Colt seating die.

I have no doubt that stork's 45 ACP dies have a roll crimp in them.

 

[Hondo 60]

When making 9mm ammo, I crimp just a touch more than taking the bell out.
So far I haven't had any feeding issues.

And accuracy has been OK - nothing to crow about.
I'm a dyed-in-the-wool revolver guy,
so I haven't had my 9 very long & don't practice much with it.

 

[noylj]

Auto pistol rounds should have a 0.001-0.003" crimp. You can look at the case mouth while you adjust the crimp die and see when the bell/flare is gone. You can run your finger along the round and verify that there is a relatively smooth transition from the bullet to the case. If you feel a sharp transition, that can cause feeding problems.
For those who have to measure everything and not learn to tune themselves, for .45ACP, the case mouth should be .451-.449". For .40S&W, you want 0.422-0.420". For 9mm, you want 0.379-0.377".
One of the "best" ways to set the crimp die is to use a factory round that works well in your gun. Simply insert the round and screw down the die until it makes "hard" contact with the round.

 

[Jim Watson]

I, too, had an RCBS .45 ACP seating die with roll crimp.
Old time accurizing gunsmith Alton Dinan favored the roll crimp and he had the machine rest targets to show why. That with SWCs that could be seated for headspace control by the bullet shoulder against the origin of the rifling, not depending on the case mouth touching the end of the chamber.

 

[GLOOB]

Ok, that makes sense. I can see a roll crimp improving accuracy.

OTOH, my experience with pulling bullets that have been over crimped with a taper crimp, they actually come out easier than uncrimped bullets. So while they may prevent setback, they don't seem like they'd do much for containing pressure.

 

[noylj]

Lee Factory Crimp Die

The Lee FCD dies for auto pistols will give an excellent taper crimp.
The die body has a carbide insert that is machined to the maximum case OD. This is to "iron out" any bulges in the case. With some oversized lead bullets seated in a case with over-thick walls, it can swage the bullet down.
For proper loads, the carbide ring should not even touch the case.
As I remember, the instructions for the FCD are real simple. You can taper crimp with the sizing die, but do not run the round all the way into the die—you just want to remove the case mouth flare. This is very touchy as it is very easy to swage the bullet down in diameter as the sizing die is made to return even the thinnest-walled case to less than minimum dimensions. A taper crimp die (or the Lee pistol FCD) will not have this same problem.
The instructions for the Lee pistol FCD are:
1) turn the crimp knob all the way up
2) raise the ram and screw the die into the press until it contacts the shell holder/shellplate
3) Lower the ram and insert an inert "dummy" round (or even just a sized and belled empty case)
4) raise the ram all the way up. Screw the crimp knob down until it contacts the case.
5)Lower the empty case and turn the knob in 1/2 turn. This will produce an excellent crimp for 90+% of all shooting needs. You can turn the knob in more or less (re-flare the case before each adjustment)

 

[GLOOB]

For those who have to measure everything and not learn to tune themselves, for .45ACP, the case mouth should be .451-.449".

Considering .451" is the diameter of the bullet, I hope you just made a typo. I understand .468"-.471" to be the accepted norm.

For proper loads, the carbide ring should not even touch the case.

This is exactly why I stopped using it. I think the sizing die should be enough to ensure the cartridge will seat, unless you're stuffing in deep-seated, oversize lead bullets. And if the taper crimp of an FCD is even more excellent than that produced by the seating die, then I'll never know until I get a turret press.