As far as I know, the FX pellets (like the Air Arms pellets) are made by JSB but with FX dyes and made specifically to FX standards. It's no coincidence that they all come in exactly the same weights and designs. The pellets are not the same, but they are made in the same place. If you try them all out you'll notice that a particular rifle will demonstrate a preference for either the JSB, Air Arms, or FX variety of the "same" pellet which speaks to the fact that they use different dyes.