Biggest issue with a bottleneck cartridge is the loss of capacity. If you are not worried about that, then it is a gret caliber to use. You do not need to by 357sig brass. Just buy regular 40sw, lube the cases, and the dies will take care of the rest. My preferred load is:
OAL 1.260
15.6gr. To 16.00 gr of H110
124gr. Berry rnd bullet
This will make 170+ power factor.
Great load, lots of gas to make the compensator work effectively.
DVC
Mark