This mould was designed especially with the hunter or plinker in mind. The bullets cast from this mould will also function through an 1886 Winchester in 45-90 caliber. Best used when you need deep penetration out of your lever gun for use in barrels with a twist rate of 1-22" or tighter. Recent production 1886 Winchesters made in Japan have a 1-20" twist. Thus this will not work in the slower twist originals in 45-90. The diameter of the meplat is .285" in diameter, overall length 1.170" long, and the distance from the bottom of the crimp groove to the nose is .370".