8mm gas check request

[JAGGUY]

I'm starting to cast bullets for my 8x56r Steyr. I have some aluminum gas checks that work fine for my 8mm Mauser .323 boolets but they don't compress down tight enough for the .329 Steyr boolet.

Any of you have some commercial copper 8mm gas checks that I could buy a few from to see if they work any better? I don't want to buy a box of 1k just to find out they don't work either..

Thanks, -greg