I've been using the 200gr factory power point with good results, but between cost and being unable to find any was looking for a good replacement load.
factory load averaged 2402 FPS
47gr TAC 2359 FPS no signs of pressure
48gr AA 2520 2359 FPS no signs of pressure
48gr H335 2455 2455 FPS with very slight cratering of primer
Testing of powder was done with 200gr Hornady RN
Ramshot X-Terminator worked better for me in the 356 Win. Ramshot sent me data for the 356 that gave a max with X-Terminator of 45.5 grns with the 200. I worked up to it with the 200 Hornady RN and it shot well with with the best group with the max load and an average 3-shot velocity of just over 2400 fps out of a 20" Winchester M94. IMR4064 shot very well but velocity was 150-200 fps less than X-Terminator.
I've also used AA2520 in my 358, I got decent velocity with the 225 but accuracy wasn't there. 48.0 of IMR-4064 gave me just under 2500 fps with the 225 Sierra and about a 1.75" 5-shot group at 100 yards.
