[cdet69]

I am thinking of trying out a Lyman 330 grain h.p. plain base bullet for a T.C.Encore in 45-70.Since it has no gas check has anyone ever used a felt wad or cardstock wad to help protect the base of the bullet and cut down on leading?

[223man]

IMHO avoid filler cards and the like..

They can (so I've heard) become sort of a projectile and dent or ring a chamber. All that has to happen is for the wad to get space between it and the base of the bullet before firing. It's not worth risking.

I'd just shoot it as-is and see what happens. Try several powders with a varying burning range.

The bullet should start out at or a few thousands larger than the bore diameter. If that condition isn't satisfied, the second best is that the initial pressure bump should upset the bullet enough to seal the bore.

Leading is usually caused (or worsened) by gas leakage past the bullet.