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The 1964-82 Winchester receivers aren't "alloy", which suggest they're not steel, when they are.
Instead of being forged from billet steel however, they were formed using sintered steel - a much less expensive proposition than forging.
The sintered receivers were first iron-plated, then coated in whatever the subject model required.
Standard Carbines received a coloration that looked like bluing; commemoratives received (variously) plating in black chrome, pewter, silver, gold or brass.
The Antique Carbine (model) received a finish that resembled CCH.
FWIW, I would recommend ridding your buddy's M94 receiver of the rust, then applying a bake-on DuraKote finish - which should give pretty good protection to a truck gun, short of spending much more $$$ on a black Teflon, etc finish.
http://www.midwayusa.com/product/197...tte-black-4-oz
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