Im getting 27fpe with the JSB HEAVIES (18gr) at 820fps. thats all i put through my xl now, they are super accurate and give me decent trajectory for up to; and including 100yds on squirells. I get 903fps out of cphp/discovery hp's. Thats 25.89 fpe with 14.3gr. So im calling BS on crosman. To get 36fpe, you need to get that 18gr nosler flying atleast 950 fps to make 36fpe. Without a bigger stronger ram, you will never see 30fpe out of our XL's and that 36fpe number is complete nonsense. My speculation is a typo error where the webmaster ment to put 26fpe, which is very realistic. Just my 2 cents guys.
Speed and weight are totally dependent on each other, as the weight increases, the speed decreases. If you go to a heavier pellet, the fpe will remain roughly the same without an increase in speed. By itself, a heavier pellet will not produce more fpe