trim 30 carbines

[MH357]

I ran new winchester brass through a carbide full sizer die now i can not fit the lee trim length cutter into the brass as well as my rcbs trimmer pilot. Any idea whats up, i have never had any problems trimming before, i tried flareing them out with the expander die a little but that doesn't help.

Mike H

[Rocky Raab]

You'll find that you probably will have to trim those cases as fired, before you size them. The carbide sizer brings them down VERY small. The next step would be to re-expand and bell them before bullet seating, but if you've already done that and they're still too small, then try slipping some fired and unsized cases over the trim mandrel. They should fit.

(Bottlenecked cases, OTH, are always trimmed after sizing, because the expander ball in those dies does bring the neck back to the correct size for the trim mandrel.)

You may find, after all this, that you seldom or never need to trim any straight-sided case, including the .30 Carbine. They just don't grow like a bottleneck case does.

[Rocky Raab]

I am very kindly advised that .30 Carbine brass not only DOES grow, but does so at a good clip. So please DO check the length of yours often.

(Thanks, Rapier. Good words indeed.)