I just bought a new mini14 target rifle with the adjustible boss like device on it.What mags work in your gun and whats you best load in this rifle.I cant wait to shoot it.It wont be long.What is the rifling twist in it?What are the best bullet weights you have tried.I loaded 500 winchester 64 gr power points just for fun and coyotes .

Hello,
Believe the twist is 1:9 which is a good compromise twist for bullet weight range of 55's to perhaps even the 75's. Most likely will shoot the 69gr Sierra HPBTM very well. Use the Ruger mags and you can now buy the 20rnd version, but not much use in a match rifle.
At local XC matches, fellow uses one of these Rugers and it will deliver 1 moa accuracy with good handloads. Might try to find some of the surplus WC846 powder, ball powder, for a lot of us around here use it and it is economical, compared to commercial powder and works well w/ LC brass, Win SR primers, and the 69gr Sierra. Use load data for BL-C2 and am told most of them use a charge of low 20's in weight, but as always check a load manual for safety reasons. Good luck!