Need Info on relaoding 45ACP ?

[mstake]

I need a little help with loading 45acp ammo. I am not new to reloading but i have never loaded automatic pistol ammo. The head spacing is differant then say 44 or 357 right. Does it headspace off of the case mouth? How close does the pressures have to be to work the action. How critical is the case length. Any help would be appreciated.

[Chuck White]

mstake

All I can tell you is that the 45 ACP does headspace on the case mouth!
That's why the taper crimp is recomended instead of the roll crimp!
Case length could be critical, but not so that you would necessarily have to trim after each firing!

Some auto's are sensitive as to where the pressure peaks, but I don't know about the 45 ACP!

[John Traveler1]

Reloading the .45 ACP can seem mysterious until you learn a few tricks.

Here's what has worked for me for over 30 years of competition shooting:

1.  Do NOT trim cases!  Even in a match conditioned pistol, trimmed cases contribute little to better accuracy.  Headspace issues develop when you mix trimmed with untrimmed cases.  Instead, keep your cases segregated by number of times fired when starting out with new cases.  

2.  Use a pistol-sized powder measure for greater consistancy.  Rifle-type measures loose consistancy when used for small pistol charges.

3.  Use medium-weight (200-230 grain) hard cast or copper-plated bullets.  The .45 ACP has shallow rifling, and hard-cast bullets give better accuracy.

4.  Avoid hotrodding this caliber.  The standard M1911 design does not do well with maximum pressures or heavy bullets (+230 grains), and gun life is greatly shortened if you insist on using hot ammunition.

5.  Use a taper crimp, not the conventional roll crimp for revolver ammunition.  If you don't have a taper crimp yet, set your crimp die to just barely straighten out the case mouth flare.  Use your sizing die (set shallow) to make sure the case mouth is straightened out.  Use a spare .45 ACP barrel as a gage to make sure your loaded ammo chambers easily.

6.  OAL is touchy for this caliber.  Even a few thousandths over max can give magazine jams or stoppages.

7.  Standardize your loads for performance and economy.  I've settled on just two loads for 98% of my shooting: 200 LSWC at 800 fps target loads, and 230 RNL to duplicate factory ball.

[Questor]

John Traveler1 is absolutely right. I can only add the following:

0) The case is big enough for a double charge to sneak in. You must visually inspect each charge before seating the bullets. Even with my progressive press, I seat myself so as to be able to make this visual inspection. This is very important.

1) The taper crimp should be to .469 to .471 at the case mouth.  I use .469 and it works fine.
2) Do not load a big batch of ammo until you have proven the reliability of your load regarding OAL and charge weight.
3) Mixed brass is OK, but avoid Amerc and S&B brands of brass because they are junk. Amerc is total junk, S&B is just irritating enough to be worth avoiding.
4) Standardize with a vengeance. If you need to change to a different brand of bullet and the dimensions differ at all from the bullets you have been using, then you need to re-verify the reliability of your loads. I buy my cast bullets by the thousands so I don't have to go through this exercise very often.
5) The only powders you need to consider are Winchester 231 and Bullseye. In fact, Bullseye is all you really need to consider.  
6) If you are loading light target loads, you cannot switch from magnum to standard primers without re-verifying the reliability of your load. There may not be enough power to cycle the action.


Most of the above advice pertains to other semi-auto cartridges as well. Although this total brain dump of ours may make the 45ACP seem very unforgiving, it really is the most forgiving of semi auto cartridges to load.

[vonfatman]

This is the best post I've seen regarding 45 ACP.

Thanks.

Bob

[Lloyd Smale]

supposidly they headspace on the mouth of the case but in all actualiy they headspace where the rim meets the extrator. thats the biggest reason trimming brass is about useless in them.

[Dusty Miller]

If your gun has an unsupported area where the case can blow out then be sure you are using good brass and keep track of the times its been reloaded.  Don't scavadge brass at the range.  Cases can and do blow out in that unsupported area and the results can be unpleasant as the dickens.