Loading for the .30 carbine

I had the exact same problem with my first bag of mixed used brass. I just ran everything through the trimmer including the short ones and loaded them all exactly the same. Everything worked fine and accuracy was no different to any other batch of factory or home made ammo. After a few more reloads, even those short cases will need to be trimmed due to growth.

You're supposed to trim them *after* resizing them. It makes a difference. (they sometimes actually get shorter when you fire them, then stretch when you resize them)

How short is too short?

Remember, 30 carbine headspaces on the case mouth.

Unlike most straight walled pistol cases, 30 Carbine cases do stretch under the firing/resizing cycle.

I only trim my 30 carbine cases that are too long. Seat all the bullets to the same overall length and then taper crimp.

I have never trimmed a .30 Carbine case in my life.

As long as they are not over 1.290" long, they will chamber in any GI M1 Carbine.

You use a taper crimp, so it doesn't matter much if some of them are longer then others, as long as they are 1.290" or shorter.

rc

zxcvbob is correct of course and just to clarify, the case length will grow over time due to being resized, not due to being fired. After a few reloads, you'll probably find that most of those short cases will need a trim.

I'm in RC's camp...........been loading that round for over 40 years and like him have never bothered to trim a case.......biggest issue I have ever had is crimped primer pockets on SOME military surplus...

All mine are used in an M/2, 2400 and a hard cast alox lubed lyman bullet.

One note I'd like to pass on to any .30C shooter is to beware of any French surplus headstamped "ve"..............corrosive in capital letters. Almost ruined an original MlA1 with that stuff years ago. I've recentlyread that some of the LC stamped stuff is not American, rather Chinese and allegedly primed with bore rot.

Well, I will respectfully disagree with you guys. The .30 Carbine cases that I work with need to be trimmed on a fairly regular basis.

Don

Yankee said:

zxcvbob is correct of course and just to clarify, the case length will grow over time due to being resized, not due to being fired. After a few reloads, you'll probably find that most of those short cases will need a trim.

Click to expand...

Actually, it is the cycle of firing and resizing that causes the cases to lengthen. It just does not show up until the case is resized.

It may be helpful to read the information the CMP has for reloading the M1 Carbine. They warn that case length greater than 1.290 may result in an out-of-battery firing. They recommend trimming cases to 1.280.

They have a lot more information on the Carbine and its reloading. Reloading for the Carbine should not be done casually (nor should any other reloading be).