I have a Browning Buckmark 22 pistol that I need help with. These guns have such a great reputation and are supposed to be great some of the best right?

The one I have snaps about half the time. I compared the spent cases with another 22 and it looks like the firing pin on the Browning is not hitting the rim of the shell hard enough.

I took it apart and found the plastic slide bumper on the end of the slide was cracked. Ordered a new one and installed it but that didn't change anything. It fired flawlessly for 20 rounds of so and then started malfunctioning again.

Does anyone know what could be causing this?
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