Joe Poyer gives the most information on the model 1892 cleaning rods.

I don't know if his dimensions are correct. He describes four variations.

Poyer gives the thread as .181"X 26TPI (I think!) and the threaded area as .475" long.

He gives rod lengths as going from 29.50", later reduced to 29.25".

He gives basic rod diameter, (not including head-area), as tapering, from .20" (behind the head) to .189" (in front of threaded area at rear).

FWIW - If I was having one made, I would get a $12 front section (of the 3-section rod) from Grandpa's Gun-parts. (The head dimensions are almost identical to the last type of model 1892 rod).

I would have the front-section rod's thread turned down to a simple pin. I would have 21.25 inches of .20" diameter rod counter-bored to accept the 'pin' and have both rods silver-soldered together.

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