As some of you know, I am in the midst of a project that started with a $30 barrel (.30 BR, 1:17" twist) for a Savage. I said to myself, "I can play with this for very little money" and "It'll be cheap, Savages are a dime a dozen". Lies, nothing but lies.
It is tough when you realize that you have lied to yourself.
I think I am somewhere close to a grand right now, and still don't have a set of dies for it. A slight modification to set of Lyman 310 dies in .308 Winchester allows me to load for it. Desperately need a stock, and probably a trigger to see its full potential. (A better shooter wouldn't hurt either).
Anyway to the point of this post: Necking either 6mm BR, 6mm BR Norma, or 7mm BR up to .30. The internet tells you to use either a stepped or tapered expander, and that is probably the best. I went a different way (remember cheap project). The expander button from an RCBS die set in .308 just splits case necks. What I found works is a Lyman 30 Short M die ($5 at a local gunshow).
So far I have done 101 Remington 7mmBR cases and only lost one. If I had been looking closely, I doubt I would have crunched that one, some of the case necks needed rounding out before expanding. I must have missed one.
It also works for the 6mm cases with a lot of care. If I were to try another batch of 6mm brass, I would put a bit more taper on the leading point of the expander plug.
Anyway, even if it has cost more cash than I originally planned, I am having loads of fun trying things out.
Robert