problems reloading for the M1 carbine

Taper crimp will allow the brass to properly headspace off the case mouth. Too much crimp will not allow the cartridge to properly headspace and light primer strikes are the result.

If you fire factory ammunition and have light primer strikes, the first thing I would check on a clean carbine is headspace.

I chronographed two loads, one using Hornady FMJ and the other using a Berry's bullet.

14.5g W296 + Hornady 110g FMJ + WSR @ 1.670” C.O.L. = 1877 fps
14.5g W296 + Berry’s 110g Plated Bullet + WSR @ 1.640” C.O.L. = 1905 fps

I contacted S&S Casting about the maximum suggested muzzle velocity for THEIR lead bullets. I was told their lead bullet should not be loaded faster than 1300 fps and their coated lead bullet no faster than 1800 fps.

Be careful when loading cartridges at carbine or rifle velocities with lead bullets.

DudleyDR said:

Some clarification on cleaning: The first thing I would check for a light strike is if there is any trash in the firing pin channel and at the hole in the face of the bolt. The firing pin may be obstructed. Crud can build up on a firing pin as well, limiting its travel. Then check the hammer spring. Of course improper headspacing or a worn step in the chamber could be a problem too.

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I agree that a thorough cleaning is the first thing to do if the carbine has light firing pin strikes with factory ammunition. If the carbine shows light firing pin strikes with reloads, I fire factory ammunition to rule in or rule out an ammunition problem.

jcb said:

Well, I am loading 115 grn. lead bullets with 14 grn. of H110. Everything is trimmed right and seating depth is .020 under C.O.L. Win small rifle primer, L.C. once fired brass.
I am using RCBS three die set and is a roll crimp die rather than the preferred taper die. My problem is light primer strikes nine out of ten times. I jsut can't figure out wha tis the problem. I have two carbines and it is doing this in both. So I think I can eliminate the gun factor.

Could this be a head space problem due to too much crimp?

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I think 14.0g is sufficient for most shooting. My carbine shoots a little more accurately using 14.5g H110 or W296. I saw no added benefit loading 15.0g, so I don't load any more than 14.5g of either powder.

Winchester Small Rifle primers work well and magnum primers were not recommended in any of the reloading material I have on hand.

The only other recommendation I would offer is to not trim the brass to published trim length. If the brass exceeds 1.290", recommended trim length is 1.280". Given that the cartridge headspaces off the case mouth, I like to trim in the middle of those numbers at 1.286".

Some people do not, but I trim M1 Carbine brass every time I reload.