If you try that Great Plains again, humor me and weight sort the bullets and weigh the powder charges equivalent to90 grains by volume. An overpowder wad wouldn't hurt either.
OK
Underclocked, I'll do that next week end, but will have to use some 385 grainGreat Plains that I have on hand - I'm out of 410s. Will shoot three 5-shot groups, one each with Triple Seven, Pyrodex, and American Pioneer.
Do you want me to stick with
90 grains volume for the 385s?
Are you sure about the overpowder wads? I have some .510" diameter, 1/16" thickCircle Fly vegetable fiber wads that I soaked with Lee Liquid Alox and dried in the sun. They work great under Lee REALs, but I've never tried them under GPs. Always thought you shouldn't use wads under hollow base bullets like the GPs.