Having just started going through this OPE McCulloch thread after Googling 'McCulloch PM8200 piston' and running across this older post, I seem to recall the above thoughts in another thread some time ago when I acquired my PM8200...., with a toasted piston, of course.
I just started searching for a piston again after a few years neglecting the matter. No luck so far, but after seeing this post, it reminded me of a similar discussion a while back and I'm wondering if anyone has actually approached such a solution? Seems like someone must have tried it, though it doesn't seem like there are many PM8200's out there to experiment with.
Otherwise, anyone know where I might be able to find a piston for mine? Only other thing wrong with it is a squirrely recoil spring. It's in exceptionally good shape overall.
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