FX Barrel on RAW HM1000X

interesting idea would like to know the outcome .the HM1000X 25,35 and 357 have all been designed to shoot the jsb pellet ,,FX rifles also like the JSB pellets too so i dont think it would matter much for that,, i got a 6 week old 30 cal HM1000X and its a tight shooter but love the idea of getting it better ,,i havent read of anybody taking the plunge yet PAT