The barrel rifling technique J helped developed is really interesting.

My Mk2 is a tack driver. Excellent gun. https://cdn.nostr.build/i/f98d416d1d6f0f0d9934a73f6ef553b0815de1e4fa08dcb3e3b4c227db8afa48.jpg https://cdn.nostr.build/i/2ba8e58011574733a9d00371a303c1e08574fc0f96186dc738aef30c6c71c32e.jpg