That @#$%^ 45º transition

[Kurt]

Well here I go again,
I didn't make a reamer for my new .38-50 Hepburn. It was chambered with the DZ reamer and after shooting 60 cornmeal blanks fire forming the cases, blowing the shoulders and necks out with the .30-40 Krag brass to the .38 caliber. I trimmed and reloaded for the final second shot fired with a full load of 3F of the old Goex Express powder I have left and a lead bullet. This did the final expansion of the cases fitting the chamber.
I shot as many rounds as I could without fouling control because it was cold and the fingers were hurting handling wet patches so I just loaded and shot. Pushing a damp patch through when loading got through I found paper rings, no surprise with this happening because of repeated shots fired without wiping.
But what I found is the paper rings will just not only damage a bullet it also can damage a case. Never seen this happen before. The bullet was a deep seated diameter PP to see what the 45 chamber end does to the shank of a bullet.
I guess it's time to get back to the drawing board and make a throated again.

[Don McDowell]

With the thousands of rounds I’ve put down range with patched bullets and the 45 degree lead I’ve yet to see any case damage like that
I’m betting there’s something else going on

[Kurt]

Don I was looking for rings because of the 45º chamber end. I looked at the patches I pushed through before shooting several rounds with out wiping. I seen some very thin still stuck on the case mouth.
I have a borescope that will reach 43" down the bore and I used it to trim the case right to the chamber end and backed it off .003" so the case would not get pulled up past the 45º and cut the patch like it would if the case is right tight to the transition.
All of my rifles that have or had a 45º chamber end I could find a paper or lead ring if I shot a GG and it made no difference if the paper was .0015" or .0023" thick. If you look for this happening you will find one.
But if you wipe between shots the rings are not a problem but they are when you shoot without fouling control.
Well back to casting