Charlie, this gun has 2-1/2" chambers, so I am loading my own shells. I have lots of reloading experience, and these are low-pressure loads. I am using new cheddite hulls and some once-fired herters ~ same problem with both of them. When I go to break the gun, it opens about 1/2 way without a problem, then it gets really stiff. Like said above, there is no resistance if I have fired only one barrel. I'm stumped.