I just tried out my new .12 ga. New Englander barrel today. It has the screw in chokes. I had the Imp. Cyl. tube in it and was using 80 grs of KIK 2f powder, a lubed overpowder fiber cushion wad, and a thick denim patched .595 rd ball. The very first shot hit in the 1 1/2" square black aiming point from 25 yds. The second shot was a little low but centered and the third was touching the first hole in the black. I then tried from 50 yds and was on the paper offhand. So if you can get some .600 rd balls you might try them. They load easy, and you get higher velocity and a flatter trajectory with the same powder charge than you do with the .690 ball.