Crimp fot the 30 M-1 Carbine

[terryt]

Hi:

I have never loaded cast boolits for the 30 carbine and would like to start.
What do I need to know about crimping?

Do the make of dies make a difference?

Thanks,

Terry

[Der Gebirgsjager]

Lee factory crimp works well (Lee). Taper crimp dies work well (I've used RCBS) and are made by several companies. I think I'd stay away from roll crimps because the cartridge headspaces on the mouth of the case and length can be important. But it will also work.

I see where you asked this question twice in a few minutes and got a different answer from each source. Not crimping is a good idea if you're going to single load them, but if you're going to fill up a magazine and shoot them I'd crimp.

[Le Loup Solitaire]

The 30 carbine case has to seat on the case mouth or it will go to far into the chamber and insufficient firing pin strike will result in a failure to fire. I put a slight taper crimp on my loaded rounds; just enough to hold the bullet but still provide enough case mouth to seat on. It has worked ok for me. LLS

[Scharfschuetze]

As noted above, the M1 Carbine head spaces on the mouth of the case so I would stay away from a roll crimp and go with a taper crimp to ensure proper HS. Make sure that you also have good neck tension on your projectile and you should be good to go. That process works a treat for me with the M1 Carbine and cast boolits, particularly with Winchester 296 and Hodgdon 110 powders.

I might also mention the extractor on the M1 Carbine as I've had various brands of cases that measured shorter than the recommended length of 1.29." Even with shorter than normal cases v. proper length cases, I've enjoyed consistent ignition and accuracy and I can only surmise that the extractor was responsible for that. The extractor on the M1 Carbine is a pretty sturdy and may hold your case well enough for a good primer strike depending on the tolerances of your carbine between its extractor and the extraction rim of the case. This is another good reason to segregate your cases by brand and if GI, by arsenal and year.

Even with the above paragraph said, I'd not depend on it and I'd strive to use cases of the proper length that HS properly, have good neck tension and taper crimp them for the best performance.

As you're considering casting for the M1 Carbine, Let me recommend my favorite cast boolit for it. It's the RCBS 30-115 SP gas check design for the M1 Carbine.