My favourite .45-70 off-hand target load of 45 years;
385 to 405 gr cast bullet
20.0 grs SR 4759, no filler
Large pistol primer (in my 1886 Winchester groups better than large rifle)
Crimped to use in the magazine, or if loaded single shot I seat the bullet out to engage the rifling when the breech block is closed with no crimp.
Estimate velocity at 1000 fps.
Very accurate in my 1886 with Lyman tang sight, when my eyes were young it would group under 2" at 100 yds off the bench.
I have some Trail Boss but haven't tried it yet.
A .457 round ball thumb-seated in the case mouth over 4.0 grs Bullseye is also a lot of fun at very short range. A tuft of cotton or kapok can be used to hold the powder toward the primer in the interest of better ignition but never use a wad leaving an air space between wad and bullet; the wad can act as a piston when fired and ring the chamber, ruining the barrel.
These loads work well in my guns, they may not in yours.
If you experiment with very low loads and manage to get a bullet stuck in the barrel, DO NOT try to shoot it out. The least you could end up with is a ringed barrel, up to a burst barrel which will destroy the rifle. I strongly suggest that any handloader read Hatchers' Notebook about bore obstructions and how to deal with them.
