45 ACP failure to feed troubleshooting - compound issues.

[ssgross]

Finally got around to troubleshooting. My reloaded range brass was resulting in a failure to feed 1 or 2 rounds a magazine in all my 1911's. No problems with factory ammo or reloads with brass that I know only I have fired (this is mixed too). For plinking, I typically use Berry's 230gr round nose. The misfeeds look like the round went in 1/4 to 3/4 of the way and stopped, sometimes straight, sometimes canted. If I pull the slide all the way back and let it fly forward, they almost always chamber.

So I set the last lot of empties aside to look at later, and well last night was later. After some reading over the last few weeks, I bought a hornady 45acp gauge and a Lee narrow base sizing die.
After sizing 100 rounds with a hornady die, I checked case length. All within a couple thous. no problem there. But, sure enough about half or more stuck in the gauge at the base. After running them all through the Lee narrow base die, they all slipped in and out of the gauge just fine. I suspected as much after reading that some modern pistols (Glocks seem to be cited most frequently) have looser chambers that can cause cases to expand further towards the base.

So, loaded up 100 over 7.6gr HS-6. Hornady combo seater and crimp unchanged from the last batch. WOW, almost all failed to gauge. After 1/4 turn more on the crimp, all but 9 rounds gauged. I pulled those to investigate more, paying close attention to how much I flared the case to make sure the bullet seated straight. I seated and crimped in separate operations this time. All but two rounds gauged now. I pulled and carefully tried to reload 3 more times...with new bullets and no dice. The fail the gauge by about 1/8 inch. After trying a few times, these two cases have scuffs where the bullet is bulging the case slightly. Scratching my head, I looked at the head stamps. In the lot, there are half a dozen or more different brass (all large primer), these 2 are the only ones though stamped "A-MERC". Digging in my empties, I found a couple more and sure enough the case thickness at the mouth is more than any others - one was a whopping 6 thous. more than the new-never-fired winchester I compared it against.

For what it's worth though, these last 2 rounds still chamber easily in all my barrels. So I think my main problem was needing the undersized die when using mixed-source range brass, and everything else was compounding. I'll also be seating and crimping in separate operations from here on out. I think the trick with Berry's bullets is to run in the crimp die until one just gauges, then gauge every round setting aside any cases that need a bit more.

Lastly, I found 5 more A-MERC cases in my bag and tried to load them. They all failed to gauge no matter what I did. In hindsight now, googling "A-MERC head stamp" tells you all you need!