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Curious about the different manufacturers that Colt has used, as well as trying to date my NOS A2 barrel.
My recent production 6933 has a 5/18 date stamp behind the gas block journal and a "R" on the barrel close to the extension. I've been told the R designates the company that made the barrel blank.
My A2 barrel just has "42" in the spot the date code would normally be and an "O" near the extension. I havent pulled apart my 2012ish 6920 yet to check the markings.
Any ideas about my A2 date and the "R" & "O" markings near the extension?
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Can't help you on the date code, sorry.
But, as I understand it, the "O" is the chrome vendors mark placed on the outside of the barrel under the handguards to signify chrome bore and chamber, a US .mil requirement.
I have them marked "O" , "R", and "W". No idea who the vendors are.