I cast my RBs for my .32 calibre. This is a very finicky calibre to get dialed in. I use a Lee double cavity mould and the RBs are .311 calibre.
My loads for my .32 is:
.311 calibre RB, 32 grains fffg, blue pillow ticking, moose milk lube. 1/2” groups dead on 50 yrds
.32 calibre maxi-ball, 45 grains fffg, beeswax/lambs tallow lube. 1” groups, 1 1/2” low at 50 yrds
There’s a lot of simple, mundane, things that can affect the accuracy of the .32 calibre. I’ve found that not being consistent in your loading procedure can cause changes in accuracy…for example lightly seating the ball on one shot, then really applying pressure on the next can move the impact point by as much as 2 1/2“ to 3” at 35 yrds.
The .32 is a very finicky calibre…Once you get this gun shooting well, and you do it time after time, over and over, you’ll be a hell of a muzzleloader.