View Single Post
Old October 6, 2012, 10:37 AM   #20
Aguila Blanca
Senior Member
 
Join Date: September 25, 2008
Location: CONUS
Posts: 6,397
Quote:
Originally Posted by Hal
Quote:
I wish they would bring back the case cannelure that formed a shelf at the base of the bullets to prevent just this sort of thing from happening.
Yeah - I agree..
Seems stupid (IMHO) to have done away with it in the first place.
You can't bring back something that never was. Cannelures are not used to form a "shelf" anywhere on a bullet, and neither the 9mm Parabellum round or the .45 Colt Automatic Pistol round originally had a cannelure.

Bullet setback is the norm with semi-automatic rounds that get rechambered multiple times. They are taper crimped, leaving the case mouth square so it can seat on the shoulder at the front of the chamber. This is how semi-autos control headspacing. It's a different animal than the roll crimp used on revolver ammo.

This problem has been discussed for years on various forums. Serious setback should not occur with one chambering, but I have never seen any round -- commercial or handload -- that doesn't exhibit setback after five or ten successive chamberings.

The one in the photo is rather extreme, but I have one on my reloading bench that's as bad, or worse. It's also a 9mm, but it's a truncated cone lead bullet. It was in a box of loose rounds the owner of the range gave me awhile back. A customer gave them to him, and he can't remember which customer so we can't even ask what the load is. My plan is to disassemble them, weigh the bullets, and reload using my powder and a known-safe charge.

Last edited by Aguila Blanca; October 6, 2012 at 10:40 AM. Reason: typos
Aguila Blanca is offline  
 
Page generated in 0.04127 seconds with 7 queries