I'm about the same way, a dozen or so M14/M1As , a single AR10, and just one 308 with a bolt. Most of my bolt guns are of 300wm variety or 30-06.
I stick to the traditional powders in the so called safe burn rate(s) (4895, 3031, 4064, TAC, 8208, BLC-2, 2000MR,etc.) for a M14/AR10 gas gun but i...