Long time since I fired any of my Sniders.
IIRC I used SPANZ brass which was machined from solid stock.
I never used substantial loads - my favourite Snider is a Cavalry Carbine. Heavier loads just end up blowing a lot of powder out the muzzle (need to do the sheets of newspaper laid out in front test).
I used an over powder thin card wad then a felt wad which was saturated with my bees wax and lithium grease brew (melted lube with felt wads in it, left to cool, removed wads with wad cutter).
I used minie projectiles, lubed, but then paper patched. I then put a slug of lube into the hollow base over the folded paper.
The projectile sat low in the case on top of the powder. Didn't look like a commercial round but shot well.
I used tradional minies (Lyman) and the Lee flat nose minie which shot superbly. Couldn't use the Lee in comps though as it wasn't in the historical spirit of the event.
Bookmarks