7760 psi is a totally realistic pressure whether the gun has Twist, Damascus or Steel barrels. The Alliant Extra-Light powder will put its max pressure where the chambers are at their thickest. If a gun won't stand this pressure, hang it on the wall or make a lamp out of it. I'm not Hung Up on all those 5K pressure loads. Of course I was always a hunter rather than a clays shooter & many of those super light pressure loads are un-reliable in cold weather.

Miller/TN
I Didn't Say Everything I Said, Yogi Berra