Well I picked up an Armalite AR-10A4 SPR. It has the 20" RH 1:11.25" barrel. I am gonna shoot paper/steel @ 500-700yds, but would still like to use the same round for bambi @ 300yds. What ammo would you guys recommend? I used the Hornady 150Gr SST Superformance last year in a FNAR @ 400yds and it worked wonders btw.