[dbooksta]

I've noticed with a lot of premium commercial ammo in auto-pistol calibers what looks like a crimp behind the base of the bullet. I guess this makes sense since you don't want the bullet getting pushed back into the case by the feed ramp.

But I've never heard of this practice for handloading, and don't even know of any tools that could do it. Are there any?

Also, wouldn't a regular neck crimp serve the same purpose? If so I assume the only reason commercial loads use the rear crimp is for jacketed bullets without a crimp groove where they don't want to hurt the jacket?

 

[fguffey]

I have reloads that have the bullet stop in the case at the bullet base, it gives my cases the appearance of having swallowed a bullet.

F. Guffey

 

[fguffey]

Are you referring to the knurl around the case.

F. Guffey

 

[dbooksta]

Are you referring to the knurl around the case.

F. Guffey

Yes, it's a circumferential knurl midway down the case, right about where I believe the base of the seated bullet should be. Here's a picture that shows it:

 

[Marshal Kane]

I have some similar cases in .45 Colt. I really like the way they look for this cartridge as they look authentic to the period. Have not seen any reloading tools offered to reloaders to duplicate this. Unfortunately, firing the cartridge and resizing the case gradually takes this out.

As you've stated, it seems its purpose is to prevent bullets from being pushed into the case although other methods such as crimping and casemouth sealant for example, works as well.

 

[TMan]

As you've stated, it seems its purpose is to prevent bullets from being pushed into the case although other methods such as crimping and casemouth sealant for example, works as well.

I don't think this has ever been a problem for me, but it would be hard to tell, as most loads that go up the ramp, head down the barrel. My thought is that you wouldn't push the bullet back very much before you had some pretty noticable pressure problems.

I know case materials in the way back times were softer and less consistant, and repeaters actually needed that to keep bullets in the magazine from being pushed into the case, ? Is the current practice more for looks?

 

[Jack]

Corbin, the folks who make bullet swaging equipment, sells a tool for applying a cannelure.

 

[dbooksta]

I don't think this has ever been a problem for me, but it would be hard to tell, as most loads that go up the ramp, head down the barrel. My thought is that you wouldn't push the bullet back very much before you had some pretty noticable pressure problems.

Depends on the powder. Some powder loads already fill the case and aren't sensitive to compression. Others loads won't fill the case but won't spike significantly badly if case volume is reduced by the bullet being driven back into them. Of course for powders where neither of the above is true it would certainly be great to ensure that the bullet doesn't get nudged backwards before firing!

 

[scott0116]

I bought some magtech cases and they have the ring. When roll crimping these cases a heavy crimp will collapse the case at the ring but after figuring out the proper crimp for the bullets i was using i have had no problems.