Playing with some subsonic loads with my Ruger American Ranch Rifle in 300blk and off to a good start. Only shot one five shot group but it measures.517 center to center so it will only get better. Top group was factory Sig Sauer 220 subsonic. Load data is LC brass, 208bthp @ 2.25, CCI 400 primer, on 11.7gr of A1680. MV is 1054avg. Gun is STUPID quiet!