Those rules must have been written by a dedicated team of idiots. Within10/1000ths of WHAT? Define bore diameter (is that groove to groove or land to land... is a .50 caliber consider .500 even though it's .502 or .498... will the agents carry calipers/micrometers?) Define exposed, pivoting hammer? Exposed on all sides, exposed in the middle, exposed on top... can it be attached to the rifle?