I’ve used Autocomp under 124 JHPs. It’s a high energy powder, burns pretty clean and has a high gas output for reliable cycling of auto pistols. Would work fine in a carbine and you’ll get higher velocities too.
HS6, Autocomp and CFE pistol all have very close burn rates, the faster being HS6, although not as fast as 231 and nowhere near the speed of Titegroup.
