But did max out a 2260 HiPac conversion with the standard Crosman valve and a prototype high power valve. Normally will set it in the sedate 15-16 foot pound area and hunt tree squirrels with it, but when I got the new valve, had to see what it could do.
[img width=600 height=219]
Other than the stock and 2240 trigger unit, it's pretty much a steeel breech 2260.
MAX TEST (max effort):
Substituted the "red" spring. Had to grind off one coil to get the gun to cock at all and the effort in cocking it is excessive.
Upper sweet spot pressure = 185BAR
Issue Crosman valve (just the piercing pin removed):
14.3gr. = 819 - 789fps = 12 shots = 20.5 foot pounds per shot
21gr. = 729 - 699fps = 13 shots = 23.8 foot pounds per shot
14.3g. = 926 - 896fps = 10 shots = 26.4 foot pounds per shot
21gr. = 810 - 780fps = 11 shots = 29.5 foot pounds per shot
Am sure more energy could be gotten (at fewer shots per fill), but it's kind of already pushing things.