Barrel for retro build? Lowers?

[garrettbragg12]

Late Colt grey will be almost black, and will actually match a charcoal Anderson lower. Lighter colt grey is a tad darker than Rustoleum primer, and early "XM grey" (the color the prototypes, early 601, 602s, and early 603s-XM16E1s were) is just a tad lighter than Rustoleum grey. With the CH forge codes on uyours, it is mid-1970s, and would be either late Colt grey, or the mid range. Check it against a black lowe.

I used my black RRA lower as a comparison and took it out in the day light. It looks to be the earlier gray?
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