I have to agree with the use of a breaching barrel. I didn't think about it because I thought you were set on a bolt-on, but the stronger barrel is the right way to do it if it ever might be used. Also helpful in glass-breaking, car-door-opening, jabbing close combatant that is unarmed...you get the picture!
“Malo periculosam, libertatem quam quietam servitutem." (I prefer the tumult of liberty to the quiet of servitude.). Thomas Jefferson
"All that is necessary for the triumph of evil is that good men do nothing."
-Edmund Burke, Loosely translated from Thoughts on the Cause of Present Discontents. (1770)