I bought a spare mag. for my WC Mk1 .25 a couple of weeks ago, it would not index or even freewheel, I determined the rear ball was crimped too deep, and the overall length from ball to ball was somewhat shorter, the rear ball "crimp" was riding on the edge of the hole the ball was supposed to ride on thus binding it. Called FX USA no problem will replace it. In the mean time I dropped my original mag. on my tile floor and messed IT up!!! I called FX USA, and they said these mag. centers are not repairable, well they expedited me a new mag. and it didn't work either, its the same as the other spare I have!!! Its obvious when comparing my original with the replacements what the issue is, maybe the Mk1's and the Mk2 mags. are different? Has anyone had this issue or shed any light on this? There is nothing wrong with the gun, it has thousands of pellets fed problem free, up until I dropped my good mag! Will call FX USA again Mon. Thanks!