Oorah! Never had to fire anything but .30 cal at 500 (M1 Garand and M14). In my experience, a keyhole with those calibers had to be accompanied by a puff of dirt from the berm! 5.56mm must be fun at 500. A belted magnum launching a 180 grain BT with 75.5 gr of 4831 at that distance performs wonderfully. Congrats to Ryan!
