Case full of drop tubed 2fg black powder, an over powder wad, seat bullet....no air space in cart. pretty simple and if done right, including proper BP lube on bullet, blow tubing between shots....it will be the most accurate load in your gun. Forget the 777 or pyrodex, it's harder to ignite and shows lots of SD, use smokeless if you must in your old Trapdoor but i don't see a case 1/4 full of powder being your ticket to accuracy. Should also mention that your bullet should match bore size and be cast quite soft, pref. 30-1.......It don't get much better!