How Do You Know When You're Got Too Much Crimp?

[Guncrazy]

I'm new to reloading, and currently reload only .45 ACP.  So far, I've loaded and shot about 600 rounds.

The bullet is a 230gr Hornady FMJ-FP on top of 5.8gr of Unique, set off by a Remington 2 1/2 Primer.  The brass is pretty much whatever I scavenge from the range.

The first 500 rounds that I loaded and shot were completely uncrimped.  The crimp die had been screwed into the press until it touched the rim of a case, then unscrewed one full turn.  The seater plug had been adjusted to create an OAL of 1.19".

These rounds fired just fine, although I experienced the occasional failure to feed--perhaps 3 to 5 rounds out of a hundred.  I wondered if crimping the necks might result in improved reliability.

The first time I tried to actually crimp a round, I crushed the case.  After adjusting the die, I tried again, and this time, I noticed that the copper jacked had been shaved, suggesting that some crimp had been applied before the bullet was fully seated.  Third time seemed to be a charm, and I was able to load and crimp a hundred rounds.

When I took this batch to the range, I noticed that they seemed to be a bit...snappier.  The report from these rounds had a sharper tone to it, and the pistol seemed to kick just a bit more in my hand.  Other than that, I had no real problems with these loads, except that I still experienced two failures to feed.

My questions are these:  First, since crimping didn't solve my problem, and I've had no significant problems with uncrimped rounds, is crimping even necessary on the .45 ACP?  And second, how do you ensure that your future crimps will be consistent with past crimps, if you ever have to re-adjust your crimping/seating die?

Thanks in advance.

[stimpylu32]

Guncrazy

First , Welcome to GBO , there are a few things to look at here , the eaziest way to get a consistent crimp that i have found is to get a Lee factory crimp die and do the crimp in a seprate step . as you have noted you get higher pressures with a crimped round as opposed to a non-crimped , being seen as more recoil and report .

I as a habit always put just a slight crimp on my handgun rounds to help prevent bullet movment from recoil , also by using the seprate crimp die you do not have to re-ajust for diffrent bullets as much . ( some more crimp will be needed if loading cast bullets )

With the FTF problem , it may be just a case of giving the feed ramp a little polishing or you can just let it work itself in as you shoot more and more rounds down range .

Hope this helps some .

stimpy

[Dusty Miller]

When you pull the handle down to crimp the cartridge and you hear a little voice say "Ouch" then you know you've crimped too much!!

[Hairtrigger]

For my 454 RSH I crimp as much as I can without wrinkling the case.
I have measured a bunch of rounds that have been in the cylinder while other rounds were fired and find that a heavy crimp is needed

[jgalar]

For an autoloader adjust the crimp so that you are just removing the case mouth flare.

[Castaway]

Sounds to me that you're applying a roll crimp to your 45 ACP.  It's not designed for that, a taper criimp only is what you need.  Save the roll crimps for the revolvers.

[gypsyman]

Guncrazy, you mentioned in the one paragraph that your loads were snapper and the guns recoil was sharper. You might want to double check the seating depth of your bullet. Your load is pretty much in the middle of the road, as far as amount of powder. But I can remember an article a couple years ago, that stated that the pressure in a small case like the 9mm/.40/.45 rises dramatically if the bullet is seated too deep, especially with a jacketed bullet. Same article mentioned seating the bullet out to touch the lands in a rifle, or single shot pistol in a bottleneck case. A small amount of bullet jump kept the pressure from rising to fast.
As far as the crimp, do it in a seperate step, and I would use a taper crimp, as that is what most of the bullseye shooters use. I can't shoot as well as them, but at least my ammo looks good in the box!! We keep trying peace, it usually doesn't work!! Remember-(12/7/41)-((9/11/01) gypsyman

[winman]

Sounds to me that you're applying a roll crimp to your 45 ACP.  It's not designed for that, a taper criimp only is what you need.  Save the roll crimps for the revolvers.

Ditto. I apply a slight taper crimp to my .380, 9MM, .38 and .45 cartridges for use in autoloaders. This greatly
facillitates the chambering process. I only use a roll crimp for heavy revolver loads.

[sangdigger]

Be carefull on crimping that 45 ACP, it headspaces on the mouth of the hull, if you crimp to much, it will allow the cartride to go to far in the chamber, and as best as I can describe it, the mouth of the cartride will be pinched aginst the end of the chamber, probaly creating higher pressure, taper crimp is the way to go. I have a seperate cartrige headspace gauge (they are about 10 bucks or so) and I slowly adjust this till it feels like there is no drag form the belled out case caused from the expander die. I also want to feel a positve stop when the case is put fully in the case gauge. 9 mm is the same headspace wise

[Black Jaque Janaviac]

Just because putting a crimp on your ammo raises the pressure doesn't necessarily mean that's a bad thing.  If your uncrimped loads were well below the safe maximum, it's possible that your crimped loads are still within safe limits.  Noticing that one reload is "snappier" than a different one isn't much of an indicator.

That said, there is such a thing as too much crimp.  I loaded some .357 Mag loads to the exact book specs of Hodgdon's Lil' Gun recipe.  The pressure listed for that max load was waaaay below SAAMI max pressures for .357.  I called Hodgdon to double check if it wasn't a misprint.  They varified it as real, and said the only reason for stopping at 18 grains of Lil' Gun was no more room in the case. 

So I made up a batch of .357s using Lil' Gun and Lee's Factory Crimp die.  Other than a batch of factory ammo, that was the first time I had to remove a cylinder and pound out a case!  I went to pull the loads and found that I had to destroy each Hornady XTP in order to pull 'em!  That Factory Crimp die put on one heckuva strong crimp. 

[Glanceblamm]

With the revolver cartridges, jacketed bullets, and the roll crimp, I would say to watch your OAL closely. It seems to be easy to jack that bullet down another .005-.007 with the crimp die alone before you will see the tell-tale signs of case buckling.

Once I  have seated the bullet in my two-step operation, I will only move the crimp die down 1/8 turn at a time MAKING SURE TO MEASURE the cartridge oal at each interval. Once you see .001 under the oal you know that this is plenty of crimp and you can back it off just a hair or leave it at that.

The cast bullets seem to be more forgiving as the longer, beveled crimp groove makes it easy to see a very good crimp…all at a lighter pressure on the handle than you would have believed.

[jhalcott]

guncrazy, We MIGHT be related or just have the same malady!
  you say the brass is picked up on the range. This brass might need to be trimmed to .893". the MAX case length is only  .898"! the 45 auto head spaces on the mouth of the LOADED case.The max COL is 1.245" . All you want to do is remove the "flare" or belling produced when you size and bell the brass. If you crimp to much you can buckle the brass. I usually adjust my dies to just flatten the bell.

[millwright]

TRIM ALL BRASS.  LEE FACTORY CRIMP DIE, NO PROBLEM.  Seriously, this works, but always trim cases for any auto hand gun.