I shot 20 rounds of PMC cowboy ammo through my new No. 1 45-70 a few weeks ago. These are 405 grain flat point bullets shot at about 1250 through the chronograph. (Very pleasant to shoot) These bullets were the first fired through the gun. They leaded it up like you wouldn't believe. About equal to 100 rounds of plain base kieths at 1400+ FPS in an unlapped handgun! What gives? I slugged the gun for feel (haven't measured) seems tight a little at the barrel band. Tomorrow I try 300 grn hornaday hollowpoints over 48 grns of IMR 4198.