My Win Classic Stainless with a 24" barrel in .300 Win Mag, loves Retumbo powder and Fed 215 primers with 200 grain Partitions. Last time I chronographed this load, using 3x fired Win brass and a near max load of 83.0 grains of Retumbo, I shot several five shot groups at varying ranges from 100 to 400 yards. Velocity ranged from 2960 to 3020 and averaged 2990 fps for the fifteen shots I took. Five shot groups at 100 yards were about 1", at 200 yards 2" and just under a 4" group at 400 yards. Good enough for me. It sure did spit fire out the end of the barrel though. Interestingly, using a max load of 84.0 grains of powder resulted in lower velocity than the 83.0 grain load in my initial load development so I stayed with 83.0 grains for my hunting loads.
