Are you considering the Lee C312-185-1R mold?  I cast that with wheel weights and add a gas check while sizing it to .312 diameter for use in my Martini-Enfield rifle.  1.5" three shot groups are possible at 100 yards when I really concentrate.  That bullet will also roll groundhogs quite handily.  That Martini-Enfield, by the way, measures .304/.312 bore/groove diameters.

I am still trying that same bullet in my Krag sporter which is more like .300/.310 bore and groove.  I size the bullets down to .311 for that Krag.  Initial results look promising.

If you don't plan to size your bullets you might want to see what is the largest diameter bullet that will chamber in your Krag without getting hung up in the neck area.  On my other Krag sporter I can't chamber a cast bullet big enough to really fill the barrel grooves which are a whopping .313".

I roll my bullets around in a margarine tub with liquid Alox and set them on their bases on wax paper to dry overnight before loading.

I am still experimenting with 2400, Red Dot, and IMR SR4759 powders to see what works best.