I use a Rainier 535 Postell mold in some 1884 trapdoor loads,the lightest bullet that worked well under 300yds is the 405gr the best load for my 1884 is 70gr of black ffg with the 500 gr round nose, the 405gr tumbles after it looses its speed. Lube is a big factor in black powder cartridges it must keep the fouling soft enough that it will not interfear with accuracy, I make my own from tallow olive oil and bees wax I can shoot more than 50 rds without losing accuracy, also a grease cookie below the bullet on top of the powder separated by wax paper at the powder/grease and .030 cork plug wafer at the top, its a lot of work but if you want the best for the gun this is what I found, Good luck keep busting caps.