Best Powder for 56-50

[Colt Fanning]

Hi,
I realize recommendations for loading have been posted many times on this site, but I would like to ask the question.
Has anyone found a more accurate powder than pyrodex P in the 56-50 for 100 yard target shooting?
I have tried Goex 2f, Swiss 2f, APP(Jim Shockley's Gold) 3F,and 777 2f.  I would like to shoot with 777 because I dont like
to swab out the bore after 6-7 shots but It produces noticibly larger groups than Pyrodex.  I shoot a cast performance
350 grain bullet (soft) with gas check in Starline cases with Win mag primers.  I have been using Spg lube in all except the
APP and 777 loads. Btw I shoot a carbine.
Regards
Colt

[Appalachian Ed]

I can shoot a 25 shot repeater match with Goex 3F and no fouling problems. Bullet lube is the key. Leave the Subs at home. Shoot the holy black

-Ed