# CRIMP ?



## rustygun (Apr 8, 2013)

I recently found some .223 rounds that I loaded were way over crimped causing a buckle. This caused me to revaluate my crimping on all the the calibers I reload. I reload 9mm,. .45 ACP, .357 magnum, .44 mag. I am a big fan of the Lee factory crimp dies and use them for 9mm, .45ACP and .357. With the factory crimp dies you will not buckle the case. I usually put a heavy crimp on my reloads that require a crimp. I was told a light crimp is better, where if you were to pull the bullet after loading it would barley make a mark on the pulled bullet that does not have a cantilure. I also was under the understanding that .44 mag and .357 needed a heavy crimp into the cantilure because of the recoil. I'm curious to know what others have found accurate and reliable when it comes to crimping.


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## noylj (Dec 8, 2011)

For straightwall pistol cases that headspace on the case mouth, all "crimping" means is removing the case mouth flare so the rounds will chamber.
I have never done any more than that for any bottleneck rounds I load.
Only revolver rounds get a crimp, and that is simply crimping the case mouth into the bullet cannelure or crimp groove. Manuals talk about light to heavy crimps, but never define the term. I have NOT found that I needed any thing more than getting the case mouth crimped into the crimp groove and NOT touching the bullet enough to leave a mark.
I only use Redding Profile Crimp dies for roll crimps.
Over crimping, as you found out, will LESSEN case tension on the bullet and you can find your rounds with bullets you can spin around the crimp.
Remember, on 9x19, .45 Auto and other semi-auto rounds, the case headspace on the case mouth.


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## Minorcan (Apr 18, 2020)

For 9mm and 45 pistol cartridges I use Lee Factory Crimp dies and have never had any issues. They load well and shoot without trouble. I don’t over crimp or use excessive pressure. Over crimping can cause more problems than expected. Just make sure the case flare is eliminated and the case is well sized.


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## rustygun (Apr 8, 2013)

I spend the majority of my time reloading for 6.5 CM and 6CM without any crimp where I even measure neck tension. Not sure where I got the idea to crimp the shit out of everything else but I see now it was wrong and could explain some accuracy issues. If I can ever find some bullets again I will load some up with light crimp. I did pick up a lee factory crimp die for .223 today.


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## noylj (Dec 8, 2011)

I find that new reloaders really seem to love to CRIMP and TRIM cases. It becomes a major pass-time for them.
Lee FCD for bottleneck cases is much different from straight wall cases. The straight wall FCD have a carbide ring to swage/size the case to under chamber dimensions. This can sometimes swage a lead bullet down. If you seat bullets straight, you'll never need a Lee pistol FCD except to bulge bust.
Never needed crimp with my .223.


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## gifbohane (May 24, 2020)

Better reloaders than me have said that the "Lee Factory Crimp Die" just covers up a poor reloading technique or mistake. I believe that to be true. I have never used one and never will.


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## noylj (Dec 8, 2011)

As far as I can see, lots of folks can't place or seat a bullet square to the case. This leads to quite a few reloads having a bulge on one side of the case where the crooked bullet bulged the case. The Lee FCD just irons this bulge out so the rounds will chamber, doing noting but ruin accuracy. This leads to folks NOT trying to find a solution to their problem and just to happily iron it out.
The solution to chambering problems is to determine the cause:
Take the barrel out of the gun (or, open the cylinder of the revolver). Drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in chamber (or gage or cylinder chamber) and rotate it back-and-forth a few times.
Remove and inspect the round:
1) Scratches in the ink on bullet--COL is too long (not a revolver issue)
2) Scratches in the ink on edge of the case mouth--insufficient crimp
3) Scratches in the ink just below the case mouth--too much crimp, you're crushing the case
4) Scratches in the ink on case at base of bullet--bullet seated crooked due to insufficient case expansion (not case mouth flare) or improper seating stem fit
5) Scratches in the ink on case just above extractor groove--case bulge not removed during sizing. May need a bulge buster.


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## pic (Nov 14, 2009)

noylj said:


> As far as I can see, lots of folks can't place or seat a bullet square to the case. This leads to quite a few reloads having a bulge on one side of the case where the crooked bullet bulged the case. The Lee FCD just irons this bulge out so the rounds will chamber, doing noting but ruin accuracy. This leads to folks NOT trying to find a solution to their problem and just to happily iron it out.
> The solution to chambering problems is to determine the cause:
> Take the barrel out of the gun (or, open the cylinder of the revolver). Drop rounds in until you find one that won't chamber. Take that round and "paint" the bullet and case black with Magic Marker or other marker. Drop round in chamber (or gage or cylinder chamber) and rotate it back-and-forth a few times.
> Remove and inspect the round:
> ...


Good info


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## Mowgli Terry (Sep 19, 2019)

Personal experience: If you notice many bullets do not have a crimp groove. These bullets are held by _neck tension._ The last I loaded of this sort was 300 gr. Sierra for 375 H&H, I do think the FDC's have a place. I remove the expanded case mouth for lead bullets in rifles with a FDC. Going ape on roll crimping puts is at risk for rounds that do not chamber. With a FDC it's necessary to look elsewhere for problems with the shoulder.

You also in handgun rounds have to do with how your sizing die works. If the die sizes your cases small you get a step seen on the outside of the case. This is where the base or heel of the bullet rests inside your sized case. Most people ignore this situation.

Another thing that can ruin your day is to be roll crimping into a groove where some cases are longer than others. Some rounds may not chamber, The easy way to deal with long cases is to trim brass.

The collapsed shoulder is a serious offender not chambering. The next serious offender is a bullet that is seated too long jamming hard into the rifling. There are other things that can make jams depending on the kind of gun.


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## noylj (Dec 8, 2011)

>Another thing that can ruin your day is to be roll crimping into a groove where some cases are longer than others. Some rounds may not chamber, The easy way to deal with long cases is to trim brass.

Never had this happen. Think it falls into the theoretically could happen but in reality never does.
Bullet cannelure and crimp grooves are more than long enough to cover any case length discrepancy I've ever seen. I set up roll crimp to be just below the top of the groove or cannelure and can NOT SEE any difference between rounds.


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## Mowgli Terry (Sep 19, 2019)

noylj said:


> Never had this happen. Think it falls into the theoretically could happen but in reality never does.


No, you are wrong yet again. Case length related to crimping is a reloading basic. This happens when the dies are set on a short case. When we say collapse it does not mean crushed. It does not take much upset there to make chambering a round hard or impossible. It's easy for the_ experienced_ reloader to diagnose this happening look for small bulge below the shoulder. When some rounds fail to chamber die setting and case length is the first place to look. That's kinda common sense.


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## DJ Niner (Oct 3, 2006)

noylj said:


> Never had this happen. Think it falls into the theoretically could happen but in reality never does.


I've seen it, but it's rare on the first firing. You see it more often on cases that have been fired 2x or more without trimming. If you shoot a max .44 Mag load with jacketed bullets and load the cases 3x, after the third firing the case length will vary enough to put an occasional crimp off the cannelure high or low (for low, it actually doesn't crimp at all, and you'll "feel" the lack of crimping action during the seating/crimping step on a single-stage press, but not on a progressive). It's even worse with old cases that had a cannelure ON THE CASE; when it straightens-out, the case gets a lot longer on the first firing and again on the first reload (used to see it a lot with once-fired Remington magnum pistol brass).

You also see it occasionally on brand-new, never-before-loaded bottleneck rifle cases, as they may not have been accurately trimmed to the final overall length before shipping. In my shooting circle, it's normal to do a full case check and prep on any virgin brass before the first loading, including OAL measurement, trim (if needed), and inside and outside deburring; and if you're a real accuracy freak, perhaps true the primer pocket and deburr the flash hole inside the case.


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## SamBond (Aug 30, 2016)

noylj said:


> Never had this happen. Think it falls into the theoretically could happen but in reality never does.
> Bullet cannelure and crimp grooves are more than long enough to cover any case length discrepancy


I've never had it happen either. My guess as to why it has not happened is that I know to check case length and trim when not in spec. 
I rely on case neck tension for my bottleneck rifle cartridges so no crimping there.
For auto-loaders (headspace on mouth) I use a taper crimp for jacketed projectiles and no crimp with plated bullets. I've found that any crimp at all when using plated bullets only makes the bullet looser in the case. This is especially true when loading thin walled 380 ACP brass with plated bullets. Talking about 380 and Nines here, the only auto's I load.
For revolver (357 and 44 Mag) I test my crimp by firing 5 of 6, loaded in gun, and inspect #6 for "bullet pull", then repeat. This needs to be done with the lightest weight gun they will ever be fired in. 
The first time I tested factory ammo this way I was quite surprised at the amount factory loaded ammo bullets will move forward under only a few recoils. Mine may slightly budge occasionally, a little, or they never move any at all. You revolver guys should test you factory ammo that way... It' eye opening.

Sam


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## noylj (Dec 8, 2011)

Again, I suspect it isn't the case length variation that is effecting the roll crimp, as I have NEVER seen it and I don't trim my pistol cases. Thus, I am either very lucky or you aren't doing what I do. I have just never seen a case length variation that was greater than the cannelure or crimp groove and I have simply NEVER had an issue. I have ALMOST reached 50 years of reloading, including a LOT of .357, .38 Spl, and .44 Mag rounds and never had any issue with roll crimping.
Sorry you do.


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## Mowgli Terry (Sep 19, 2019)

OP had run into a problem with collapsed shoulders on 223 and was asking about crimping on his handgun rounds. I feel comfortable the the question of collapsed shoulders is addressed very well. Set the dies right and it won't happen. That's the quintessential no brainer.

Added. Can you really set the crimping die correct for a roll crimp with different length cases. No-brain er #2


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## Mowgli Terry (Sep 19, 2019)

noylj said:


> 3) Scratches in the ink just below the case mouth--too much crimp, you're crushing the case





noylj said:


> Again, I suspect it isn't the case length variation that is effecting the roll crimp, as I have NEVER seen it and I don't trim my pistol cases. Thus, I am either very lucky or you aren't doing what I do. I have just never seen a case length variation that was greater than the cannelure or crimp groove and I have simply NEVER had an issue. I have ALMOST reached 50 years of reloading, including a LOT of .357, .38 Spl, and .44 Mag rounds and never had any issue with roll crimping.
> Sorry you do.


I really love consistency. "Never" is a long time.


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## noylj (Dec 8, 2011)

NO, never is from the start until now.
My never is not the same as your never.
Some day, my never may end or it will end with my death.
I suppose, to make you happy, I should use "not yet" rather than "never?"


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## Mowgli Terry (Sep 19, 2019)

noylj said:


> NO, never is from the start until now.


What does this have to do with anything. Basically, you have contradicted yourself in a hostile manner. I do have my doubts that you are reloader by your nebulous statements. Specifically, I'd suggest you review the character of 50/50 lube.


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## VAMarine (Dec 25, 2008)

Have removed 3 posts.

Don't act like jerks.

Sent from my SM-G955U using Tapatalk


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## noylj (Dec 8, 2011)

50/50 lube: 50/50 Beeswax and Alox 2138f grease (not the surface coating material in LLA).
Did I pass?


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## Mowgli Terry (Sep 19, 2019)

Thanks for your efforts. NRA or 50/50 is a wonderful lube but is soft. In the handling it is possible to have a thin film on the bullets. From what ever the source lube will build up in bullets seating or crimping dies. In my experience 50/50 can build up in case gauges. Going through a Lyman 4500 this lube does not need heat. Is that OK?


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