i don't understand the differences in these guns. mine is .22 cal. i always try several different pellets in a new gun to find out what mine likes. i have the cp's in the cardboard box, jsb 15.8 exacts, rws super domes and superpoints. all the pellets shot decent but the jsb's shot half the group size of the second best (cp's in the cardboard box). the furtherest i've shot so far is 80 yards, gonna try it at 100 soon, and it easily groups the jsb's under 3/4 inch. i believe it'll easily group them an inch or under at 100 yards if i do my part. my rifle was manufactured sept. 09. i do pick thru the jsb's and find the ones that don't have deformed skirts to do my testing. i guess it's the softer lead but a lot of them have bent skirts. i need to make me a tool to straighten them i guess. sure do hate to discard up to a 1/3 of a can sometimes. so far i love this gun.