60 grains of 3031 with cotton ball and grits as filler (didn't have any corn meal) was better.  Cleared the barrel but was still way too light.  Test loads with 3031 and a felt wd instead of cotton ball,some with IMR4350, and some with IMR4320 are loaded and waiting for a trip to the range. 

I'll keep you posted.  No luck finding teh other powder yet.

I tested three loads in the 500 express last night between rounds of shooting trap. 

I fired two cartrdiges with 65 grains of 3031 with a felt wad and filler up to the cast 325 grain projectile.  At 25 yards they hit paper about 9 inches high and an inch apart.    I really can’t ask for anything better than that.

I didn’t get good ignition with the 4320 load, but 60 grains of IMR4350 performed solidly as well.  Those slugs hit about 6 inches high and 3 inches apart at 25 yards. 

One of the 4320 load projectiles failed to clear the barrel which gave me the opportunity to drive it out and put a caliper on it.

The barrel diameter is .503

I think that is fantastic news because it opens the entire inventory of 50 caliber muzzle loading projectiles up to me for loading in my cartridges.

This is going to be fun.

All of my test loads to date have been light and the heavy gun soaks up all of the recoil.  She is a pleasure to shoot and I am very pleased so far.

glad to hear you are making headway.  Let us now if you have any other questions.

Thanks guys!  I'll keep you posted as the project unfolds.