.45 Colt sizing for .45 ACP lead


October 29, 2013, 05:04 PM
For .45 ACP loading, I have gotten my .452 (measured) lead bullets to stand better for seating by sizing the cases with my .45 Colt sizing die. The finished cartridges drop into the gauge better than ever, and I don't get the bullet imprint through the case.

I seem to be getting better bullet alignment with the case, when it isn't crammed in quite as tightly as with all .45 ACP FMJ dies.

I have measured the finished rounds, and they do come out about .001 larger than before, measured below the crimp, which setting was not changed.

The sizing die is Hornady of recent vintage.

For context, I decap and prime on the press. The cases were run through a .45 ACP Bulge Buster before loading. I decap/size, prime, charge/expand, seat, and crimp on the press, all in separate stations. The press is a Hornady LnL AP.


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Don McDowell
October 29, 2013, 05:22 PM
If it's working, and you are getting decent accuracy and the gun functions, don't fix something that isn't broke.

October 29, 2013, 05:42 PM
As long as you have adequate neck tension, and the founds fit your chambers, you'll be fine. You may find neck tension to be inadequate with RP cases.

Is the bulge buster tighter than the .45 Colt sizer?

October 29, 2013, 07:51 PM
It results in the same variance between bullet diameter and case ID as for any other caliber (.001). It's .45 ACP that has .452 bullets for .450 die sets resulting in an .002 variance and loading headaches from equipment intended fro .451 bullets.

There is the same resulting neck tension as would result for FMJ at .451 using all .45 ACP dies. I did do a push test with the lead right after sizing. I found no problem. The bullets didn't budge.

I was using Hunter Supply 200g LSWC bullets verified at .452.

The Bulge Buster uses a .45 ACP FCD post sizing ring. The purpose was to do full length sizing before loading, trying to ensure the case was not involved in any gauging failure prior to the actual loading process. I dropped the cases in the gauge before using them and after sizing. I do have some new cases but haven't tried those.

October 29, 2013, 07:58 PM
I do that with my 38 Special HBWC loads... size with an oversize sizer die that gives me minimum tension.

October 29, 2013, 08:24 PM
I have three .45 sizers that I do not use. One is about .461, which is too tight, one is about .465 which works with thicker brass, but is too loose with RP brass, another is about .463, which works well, but leaves a pretty good coke bottle look. My other sizer that I use is about .464 and works well with all brass without much coke bottle look except for some really thick brass, yet still gives adequate neck tension with the thinnest brass. My .45 Colt sizer is about .466.

October 30, 2013, 10:31 AM
I did a lot of measuring, and the simplest way for me to state the results is that the sized cases of various headstamps using the .45 Colt die are .001 larger than the cases sized with the .45 ACP die.

I took a bullet measured at .452 and turned it point down and hammered it into a case sized as .45 Colt. It didn't go easily. I did some inconclusive measuring but most of all it took several good whacks to get the bullet out using an inertial puller. That bullet isn't going anywhere, and I see no reason to be concerned about neck or simply case mouth tension. If there would be any case tension issue, it would have to come later from the expander, which of course remains .45ACP.

BTW, Peter at Lee said that they might be able to return to doing some custom die work after the first of the year.

October 30, 2013, 05:52 PM
I took another tack later today when my M-die arrived. I put the .45 Colt die away. The original problem was getting the lead bullets to sit straight for seating. That now seems to have been solved.

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