this post was submitted on 12 Nov 2025
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Working on getting my MP22k from GCI running. Basic firing function (stripping rounds, chambering, and firing) is working fine but I'm having some issues with cycling. The biggest problem at the moment is ejection. From what I can tell, extraction is reliable but the casing isn't being properly kicked out through the ejection port. This results in a jam every shot or two. The manual says to start by removing material from the inside of the extractor arm so that it grips the casing more tightly, which I have done but I'm still having the same problem. My current plan is to continue incrementally removing material but I wanted to check if anyone had some experience or insight. Any tips appreciated.

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[–] Aeroiche37 1 points 2 weeks ago

That seems really odd, are you sure that your bolt weight is fully seated into the recess in the bolt? I had no issues with bolt travel without touching the length of the recoil spring.