I just started working with a .375 JDJ and just resized all my brass, but didn't know what the consensus was on shoulders. Should you push the shoulder back until it sits flush with the end of the barrel, or only until the barrel and frame close without trouble?

I have the shoulders pushed back until it just barely protrudes from the end of the barrel, but with the barrel on the gun, it still closes easily. Is that right or should I bump them back until they lie even with the end of the barrel?

I've read Mike Bellms article, but I wasn't clear if you should try and take up that barrelframe gap with properly sized cases or not.

Sorry for the long post, just looking for a little educating!

Thanks!

I shoot several Contenders and Encores including 257,309,&358JDJ.I have found best accuracy with the base of the cartridge flush with the end of the barrel. I did the neck sizing and partial sizing thing and ran into vertical stringing. I know it is not the best for brass life but I have ALOT of firings on these cases.
You should see that barrel soon.
My 2 pennies,
Darryl

Check out the article on Bellm's web site entitled "The experiment every contender owner should perform." It addresses this pretty well.

Bellm's article

steve

You first have to know what the barrel-to-frame gap actually measures, then sized cases should stick out of the barrel about .001" less than this amount so there is some clearance on the case head as the barrel is closed..... ie, headspace.

To answer your question, yes, for the sake of case life, take up most of the gap, but leave just a small amount of headspace.

The more you push shoulders back, the more the cases will have to stretch, but at the same time, you do not want to be jamming the case into the chamber when you close the barrel.

The "size it til the barrel closes easily" method is ok, but you still do not know exactly what you have..... it is a guess and by golly method which is easily improved upon with basic measurements.

When going by "closes easily," you don't have the first clue if the headspace is .0005" or .005." When .006" is the generally accepted MAXIMUM headspace, it is easy to exceed this with guess work as your only guide.

Mike Bellm