I have had this happen to me a couple of times with pellets as well. Aside from now carrying a fiberglass rod in my case now to tap the jammed pellet back into the magazine, I also did some experimenting with the different magazines to figure out why it happens and completed the fix for it.
What happens is the very edge of a pellet head will catch this sharp edge of the magazine as it begins to exit. (Check out the difference in the two magazine holes, before and after.) This sharp edge is sometimes catching/dragging the edge of the pellet's head, which allows the pellet to want to move sideways in the magazine. Then, the extra force we apply with the cocking lever jams things up. Through testing, the solution was to cut, radius and polish the leading edge of the hole in the magazine. I haven't had a jam since, and can feel that there's no catching issues anymore.
Cleaning and polishing up the inside edge of the hole was easy enough with these steps: (1) Disassemble the magazine. (2) Working from the outside to reach the inside corner of the hole at an angle, take a razor blade and lightly cut the sharp corner off the hole. One or two light cutting swipes all the way around the hole worked. (3) Polish the cut edge into a smooth round radius with 400-600 grit sandpaper (I rolled sandpaper tightly around a small .050" Allen wrench to work the close corners and add pressure to the paper.) (4) Reassemble, tightening the screw so the magazine lid is closed on all sides and rotates with a little bit of resistance.
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then I'll report back, I'd love for all 4 of my mags to work, not just 3.
First 11 shots over the chrono looks very promising (JSB 18,1gr).
