Hi I,m looking for a smartparts freak BACK BARREL. I do,nt know if fact that inserts in kit i have ordered are aluminium make any difference to barrel back or not! Anyway i looking to buy a back barrel or if anyone's looking for a ion threaded smartparts freak back barrel and has a S P F BACK BARREL AUTOCOCKER thread I will be more than happy to do a straight swop But really I,m looking for two back barrels autococker thread but not much chance of getting two in one go,LOL thanks for your time.