Hi Michl,
Can you expand your explanation some further ?
... Or illustrate it with specific examples ?
Considering the length of this device as having 90 cms, we may assume the thinner section has some 50 cms and the thick part the balance 40 cms. To my ignorant eyes the first is too short for a (soulder gun) barrel rod and the second too long and sturdy (9 cms) for a muzzle plug.
I can easy assimilate that, the brass (not iron) threaded part makes sense for the application of cleaners or extractors (as i previously noted), but the whole ensemble makes me puzzled

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Looking at the superb pictures you posted, i still don't get it; maybe i am blocked ... wouldn't be surprised
Richmond, what is the thickness of the thin section ?
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