Perhaps this is what you intend, but I have seen a few Mausers that had round-to-octagon barrels. Which is to say they were round at receiver face and became octagon at the forearm tip. Exactly backwards of what I associate as "normal". They looked pretty good, though I can't say that I would have ever thought to do that since my experiences have strongly biased what I think is the right way to do it.

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BrentD, (Professor - just for Stan)

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