You have it, Argo. As you have learned, choke is constriction measured in thousandths, not a muzzle measurement. So, to determine constriction, you must have a bore measurement at the start of the constriction and at the end of the constriction. Muzzle is not necessarily the maximum constriction. You will need a bore gauge if you want to really measure choke constriction.

DDA

Last edited by Rocketman; 06/23/16 10:22 PM.