Roll Crimping Cast 45ACP?

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Does anyone do this? Forty years ago, my 45 RCBS die set came with a seater die that roll crimps and I used it that way for many years. Way back when, I bought a separate Taper Crimp die and have used that since. I am now finding that the TC die is not holding cast bullets firmly in R-P brass cases. Would reverting back to the original RC seater be a good idea in order to continue loading the R-P cases. I have a lot of them.
 
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Since the .45 ACP indexes on the case mouth, a roll crimp is not a good idea. Can you increase the taper crimp a little? What diameter bullets are you using?
 
If you roll crimp you may well be relying on the extractor to hold the case in position when in battery. Not the best idea from a reliability standpoint.
 
I’d try a dummy round and see how it feeds. I seem to recall Remington brass being on the thin side which would cause that problem especially with under sized bullets

Exactly, I only have this issue with R-P
 
If I wanted to continue using the brass in question, I might take the expanding plug and make it about .001 smaller in diameter

That will increase the neck tension[/QUOTE
Great idea, I’ll try it slowly
 
I won't argue the matter, but I've shot quite a few roll-crimped .45 ACP rounds with cast bullets and they worked fine in several pistols. Some years ago, I bought a Star Universal press from the '60s set up to load .45 ACP. The included crimp die was for roll crimping. I prefer taper crimping as I've seen slightly better accuracy with such a setup.

I have a brief AMERICAN RIFLEMAN report from the '60s written by one of the foremost .45 pistolsmiths of the era (and perhaps a Bullseye competitor as well), Alton Dinan. He suggests a roll crimp on .45 ammo. It appears this manner of crimping apparently fell out of favor, but it may be worth experimenting with for those who have not tried it.
 
No doubt as a general rule, they may shoot fine, but this is the same as shooting 40 S&W out of a 10mm barrel.

Building on Joe44VA, headspacing with the extractor can also cause premature wear of the extractor and ultimately failure. Best to stick with headspacing on the mouth of the case by taper crimping.

45 ACP brass is easy to come by, no need in trying to salvage brass that is causing issues by introducing another variable that may cause other issues. If there was a 45 ACP brass shortage, then maybe this would be something to look into.


Rosewood
 
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Under certain circumstances the roll crimp works better, you just have to try both. One thing to keep in mind, if you shoot lead bullets with a shoulder, leaving some shoulder exposed above the case mouth, will have the advantage of, the round headspacing on the shoulder, instead of the case. How the barrel is throated, will determine how much of the shoulder to expose. If this is done, a roll crimp will not affect the headspace at all. Bullseye shooters have done this for years.
 
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When I started loading .45acp, I used a .45 auto rim die set which applied a roll crimp. I used just enough crimp to remove the flare and push the case tight against the bullet, but didn't press the case mouth entirely into the bullet. My intention was to leave enough of the case mouth showing to serve for headspacing. I don't remember using R-P cases for this, though. GI brass is what was mostly around.
 
Your 40 year old RCBS die might roll crimp and taper crimp both, depending on how deep you adjust it down.
 
A lead boolit needs to be at least .4515. You can adjust the crimp die down and then adjust the seating part. A-merc is the only brass that I chunk in the scrap pile. Try resizing the brass and then seat a bullet to test resistance. Maybe an adjustment will fix. If it used to work it should work now. Be sure to drop a few in the barrel and flush with the hood.:)
 
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Thanks to all who replied! The combined knowledge and experience of our membership is priceless.
 
I've roll crimped plenty of cast lead 45ACP over the years. I just field striped the gun and had my barrel handy on my bench and did the plunk test and compared the chamber seating depth to good factory rounds. If the same then you should be good.
 
I've roll crimped plenty of cast lead 45ACP over the years. I just field striped the gun and had my barrel handy on my bench and did the plunk test and compared the chamber seating depth to good factory rounds. If the same then you should be good.

Now, I can agree with this!
 
I've never had a problem with my RCBS taper crimp die creating loose bullets in 45 ACP with any brand of brass. Taper crimp is designed to remove the case mouth flare after the bullet is seated, it is not supposed to provide bullet retention. If the seated bullets are moving in the case, then either the expander plug is too large in diameter and/or the bullets are undersized.
 
I am now finding that the TC die is not holding cast bullets firmly in R-P brass cases. Would reverting back to the original RC seater be a good idea in order to continue loading the R-P cases. I have a lot of them.

R-P is known for thin case walls. I use them exclusively for .452" cast bullets. .451" plated was yielding too many loose bullets in the R-P brass. What is the diameter of your cast bullets?

Taper crimp isn't meant to hold the bullet. That is the neck tension's job.

You don't roll crimp ACP ammo.
 
Roll crimping 45acp would only be suitable for revolvers. RP brass is thin. If you are shooting 0.451" bullets, they are really too small. GO to 0.452" bullets & RP brass is fine with a taper crimp.
 
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