I received a free MCK from a guy at work, no box or papers nothing, he claimed it was for a model G20 but I can't get my Gen 3 pistol to fit.

The charging handle is embossed GL21 but the markings inside the shell itself reads: GL 17-18-91-19X-22-23-31-32-45. The rear retainer door thing is marked GEN 2 and GL 17-19.

I'm thinking that the charging handle got swapped since it does fit the G20 slide but the housing is not long enough to accept the 10mm pistol. I can get the gun up in the housing and the rail slot on the frames dust shield locks up but the slide is slightly retracted and the retainer door won't close & lock into place. Yes I moved the muzzle piece to the forward position and I can see a white F stamped on it that is now exposed.

Any ideas besides Tannerite?

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