be careful for polymer pellet.
1. polymer cannot leading of the rifle. lead the rifle is a must have process for break-in the barrel, and a key for accurate shooting.
2. polymer is harder than lead --> its chip may damage the rifling. while lead dust deform easily since it is very soft.
3. JSB is a good pellet for shooting competition. so far, no poly pellet be used in competition yet.
4. too light for hunting. I use 10.34 grain JSB 177 pellet and kill rabbit over 50 yard head shot consistently. use heaviest pellet your gun can handle accurately. not the light one. http://www.pyramydair.com/s/p/JS ... ins_Domed_500ct/388
2 cents.