I no longer have my .244 or .243. IIRC, RL-17 showed some good numbers in those rounds.

With the new StaBALL now out, I'd try that one as it's pretty close to 4350 burn rate. Hybrid 100V is the velocity champ in the .257R, although not the most temp stable. Not sure how it'd do in .243/244 rounds.

New powders can to some good things in old rounds.

DF