AFAIK, nobody makes a commercially-available dovetail slot filler blank that is round on top, to fit a barrel contour, most likely because there are too many different contours on various rifles.
You would have to fit a flat-topped one, then file it to shape, and cold blue it to match your rifle.
Alternatively, I've seen some slots that owners had pounded in a .45 cal lead bullet, then shaved the lead down to barrel contour, then just let it oxidize naturally.
Although I've bought commercial, flat-topped slot filler blanks from Lyman, Marble's & Williams - I've had better satisfaction from filing my own out of the dovetail portion of an old longleaf rear sight.
Here's a tutorial, for making your own slot filler, as above:
http://www.gboreloaded.com/forums/index.php/topic,176177.msg1098837317.html#msg1098837317The receivers were molded/cast of powdered/sintered metals, then iron plated to take either a coating that appears to be bluing, or a chrome plate of some kind (black chrome, gold, pewter, silver, etc). Some (the Model 94 Antique) were even coated to look like color case hardening.
Also AFAIK, most home refinishers apply one of the spray & bake finishes from Brownell's, like Dura-Kote - which leaves the receiver a subdued black semi-gloss.
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