hi got a hatsan 3, 1/2in magnum the lad that sold me it Sade it would also take 2,1/2in cartridges but when i took it out for a shot it takes the first shot ejects and the 2nd cartridge won't fire ie the first cart hasn't shoved the cocking system back far enough tried it with 2,3/4 AAA and the same no joy, i have never tried 3 or 3,1/2in yet as it may just take them what yous think lads.