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Johnny Guest · November 25, 2002, 11:00 AM

What kind of crimp are you using, Neal? If the case length is minimum, and the chamber is toward maximum permissable length, these two factors could combine with a too-aggressive crimp to create excessive headspace.

The .45 ACP ctg normally headspaces on the case mouth. Using a very hard taper crimp on a lead or plated lead bullet might allow the ctg to go too far into the chamber. Same with a roll crimp rather than a taper crimp.

Taper crimp should only straighten out the case "bell" effect, not create a visible constriction of the case mouth. If loading thin brass, you mmight need a smaller expander plug to have brass hold bullet in place. Another argument for sorting brass before loading.

I got a "bargain" on some very old once-fired brass a few years back. Headstamp was Rem-UMC, rather than R-P. I'm reliably informed that this brass was a good deal thinner-walled than usual. Calipering case wall thickness, compared to some Speer and Federal brass confirmed this. I ws okay using thazt brass with cast bullets sized .452, but NOT with some jacketed (not plated) bullets which ran .451 to .4515. Yes, a very small difference, but made a difference in the seating and ullet security. Finally shot all that brass up in a Thompson SMG and lost it in the pasures.

Best of luck - --
Johnny

November 25, 2002, 11:00 AM	#4
Johnny Guest Moderator in Memoriam Join Date: August 28, 1999 Location: North Texas Posts: 4,123	Uhmmm - - - - What kind of crimp are you using, Neal? If the case length is minimum, and the chamber is toward maximum permissable length, these two factors could combine with a too-aggressive crimp to create excessive headspace. The .45 ACP ctg normally headspaces on the case mouth. Using a very hard taper crimp on a lead or plated lead bullet might allow the ctg to go too far into the chamber. Same with a roll crimp rather than a taper crimp. Taper crimp should only straighten out the case "bell" effect, not create a visible constriction of the case mouth. If loading thin brass, you mmight need a smaller expander plug to have brass hold bullet in place. Another argument for sorting brass before loading. I got a "bargain" on some very old once-fired brass a few years back. Headstamp was Rem-UMC, rather than R-P. I'm reliably informed that this brass was a good deal thinner-walled than usual. Calipering case wall thickness, compared to some Speer and Federal brass confirmed this. I ws okay using thazt brass with cast bullets sized .452, but NOT with some jacketed (not plated) bullets which ran .451 to .4515. Yes, a very small difference, but made a difference in the seating and ullet security. Finally shot all that brass up in a Thompson SMG and lost it in the pasures. Best of luck - -- Johnny