This mould made for the fifty caliber barrels being made today for use with a 36" twist rate or faster. Great for hunting or plinking. The nominal dimension is .510", the meplat diameter is .330" which will create a wound channel necessary for a quick kill. The bullets overall length is 1.01", bearing surface length .590". The above information is for a 20-1 alloy. Other alloys will vary slightly in weight and dimensions.