This Might sound funny to you guys...But this is my observation of my .22 Disco. from a from a 2000psi fill up and shooting down to about 1000psi I get about 30-35 shots average. (using different pellets)
But When I only use the JSB pellets, I get about 40-45 shots from that same fill up. I've noticed that these jsb (14.3,15.8) fit tight in the barrel, have a wider skirt, conserve air better. that's probably why these are more accurate then the crosman premiers in my gun
The CP don't fit as snug, have a smaller skirt (even though they shoot okay) they use more air, and i noticed when shooting these pellets my gun is louder ( I have a TKO ) so I can tell the difference. I can actually see the extra air come out the barrel when i shoot these.
i don't have a chrony yet...but i'll bet the jsb fly faster and hit harder!