I know this may sound stupid but have you tried different ammo.
We have 2 Marlin XT model 22 magnums, one is the MVSR the same as this and the other is the basic standard synthetic model. With both of these we had numerous problems with failing to extract using Winchester ammunition. We changed to CCI and can't remember when we had the last one. Some of the Winchester cases would have a very fine split near the top of the case after firing and these were the ones that always stuck in the chamber.
I even tried bending the angle of the extractor claw to a slightly greater angle which helped a little but we didn't fix the problem until we changed ammo and have never looked back since.
We use CCI Maxi Mag 40gr HP.
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