Can someone measure the od of a good round at the crimp for me?  Also what brass is it?  

I don't have any factory ammo to measure.  My first set if reloads were really bad on es and I am hoping it is an issue between the crimp and coal.

I am using rmr 110g rn and w296 w/cci sr primers.

I haven't reloaded .30 carbine in years, but I remember the two things that I found that were important. first the only crimp that can be used is a tapered case crimp, and also the case length is very important. This is due to the cartriidge chambering off of the case mouth and not the actual chamber. Very similar to the 9mm and 45acp.

LC 72 USGI ammo 0.332 at the edge of the case mouth and behind the crimp.

The proper crimp on 30 carbine should measure the same as behind it. It head spaces off the case mouth like 45 ACP, 40 S&W and 9mm Luger. Changing amount of crimp is not advised and likely will not change ignition. Increasing crimp will just deform the bullet and reducing crimp may cause feeding issues with the case mouth hanging up.

Curious why you care about es for 30 carbine? Most rifles chambered in it, 30 carbines, are not precision accurate. It also is not a long range type round where you will see vertical spread.

Thanks for the info.



Well the first patch of 15 I shot had a good side to side spread but stringed vertical.  I would say 1.5 moa side to side but over 6 moa vertical.  Es was over 80.  Just trying to figure out what the hell I did wrong.  

Fyi, on precission stuff my my es is usually single digits.  I knew this would be high but not expecting that high.

Running a ballistic calculator for the Sierra 110 you would only get a 3.6” difference in elevation for a 400 fps change in velocity at 100 yards and less than 1/2” for 80 fps change in velocity.

6 Moa is not bad for a carbine. Winning scores are not that stellar for them. According to Brian Williams, the national matches carbine match winner, “ The great thing about the M1 Carbine is that as long as you have a good ammo supply this rifle can shoot. Honest. I have had countless numbers of people that tell me that there is not an M1 carbine that will shoot. I can tell you from experience that they will, but you are going to have to put in some time with one to learn how to get it to shoot where you want it.”. I got to shoot with him at a match and talked with him about what he shoots for a carbine. Besides a new barrel and carefully fitted new production stock, he told me basically the same as I quoted above. They are finicky how you shoot them.

I did 14.5, 14.7 and 15g, all seemed to be common loads.  In thr first test 15g did the best and iirc was the mil loading.