Sometimes they do...mostly it's the transfer port seal (rubber gasket between the gas tube and the chamber). Most are squished and mangled to a tiny little opening, the ones that aren't let more gas into the chamber. I'd not strangle it to get back to the 12FPE limit, would consider shortening the hammer spring. Would give an added bonus of slighly easier bolt manipulation.
That level of power is quite rare in a non-tuned gun, but not unheard of. Have played with five of these rifles extensively, and of the 5, one was putting out 11.6 foot pounds as issued. That's the only one I've never been inside of; that level was just what I was looking for.
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Guess it all evens out. One would cough out a 14.3gr. (.22) pellet at all of 495fps as it came from the box...not really going to accept 7.9 foot pounds. That one had the double problem of a nearly squeezed close transfer port seal AND a very rough gas tube. That rough gas tube was slowing the hammer...worse, it was slowing it randomly, so the variation betwen shots was sky-high.
