Kentucky 40 cal percussion pistol help

[Richard Dittman]

I have a 40 cal Kentucky style percussion pistol with a 10 1/2 inch bbl. My problem is I can’t get it to group at 50 yds. It groups fairly good at 25 yds using 15 gr Schuetzen 3F powder, 85 gr cast 390 round ball, and .018 pillow tickling patch with 6:1 water to ballistic lube. I tried both 390 & 395 diameter RB with .010, .015 pre-lubed patches and my own patches, but nothing seems to work. I would like to know what other people use

 

[Sam squanch]

Try weighing your bullets to find the light weight ones, and discard them. Up your powder charge and use a wad or cream of wheat between the patched ball and powder.

 

[Jim in Wisconsin]

What is the rate of twist in your barrel?

 

[Richard Dittman]

I’m not sure of the twist rate. It is a rice barrel. I believe it is 1:20.

 

[Flintandsteel]

Probably up you powder charge.?

 

[64Springer]

15 grains is a mouse fart.

Maybe the balls have run out of steam at 50 yards.

And are beginning to wander.

Try 30 grains.