It sounds like you have a good rifle but I think you should be able to beat the 3300 with a 175. Since you have tried the 25 and H100 I would think that you should try still slower powders. The customer who had the 7 Ultra with the 26" barrel and 175 grain bullets is on the road right now but he usually calls and checks in or stops at the shop when he gets in. If you would like I will find out what his load was it could well of been 870 but I can not remember. Your velosity with the 140 sounds in the ball park depending on temp. You may find it rather intresting to shoot through your chronograph and see the difference in velosity between lets say 90 degrees and 18 degrees. Some loads will be as much as 150 fps different depending on the cartridge.