So i just recently received back my Daniel Defense MK18 from a barrel swap at the mother ship. It worked perfectly before the swap, but I had some overgassing with my suppressor on it. I now have the newer barrel with the considerably smaller gas port. It still runs like a sewing machine. Also swapped out my optic mount and weapon light after I got it back and sighted it in. The can in question is a Deadair Sandman S. I actually maintain and zero all of the department issued pool rifles at my station. I just refuse to carry those because I see how guys treat them. What does everybody else carry as a personal duty rifle, if in fact you carry one?