Did some light reading on the 22CM. What I read, keeping the projectiles 3200 and under seem to prevent in flight jacket separation and extend barrel life to 1200rnds. Of course, you can turn up the velocity on the Hammers. LOL
I start Hammers .020 and usually end up .050ish. Sounds like a plan.
Popular powders are H4350, RL23, RL16, RL26. H4350 and RL23 seem most efficient.