Interesting,I tried RL-15 in my Whelen and was getting 2200+. The max I found was 53.0 grs and that is what I worked up to. May try RL-15 with a 220 gr Speer just for fun.
I'm using 55.0 grs of Var-Get,250 gr Speer,CCI 200 and from a 22" barrel,the velocity is just over 2400 fps.