Redhawk1, It looks like if I keep vel. below 1000 fps. it doesn't have a problem. I tried reducing my Unique loads to 14 grs., and velocity was still crowding 900 fps. which surprised me again. With 14 grs. I need a filler, or the occasional shot produces a big velocity variation (100 fps.). This Trailboss stuff is so fluffy that it fill the case at the speed I want. No fillers, and very consistant, a perfect combo. For an oddball gun/cartridge combo that I was worried I wouldn't get any performance out of, this one is surprisingly easy to get going, the biggest problem has actually been slowing it down with a reliable load. Thanks