Another Barrel Question

[Mark Hitchcock]

I have a barrel marked "Colt 45 Auto" at the 7 o'clock position on the left side, "P" on the left lug and a "F" on the underside of the barrel just forward on the lugs. I think it goes in the Colt S/N range 712350 to 2 Million. But the color is grey/green parkerizing. Is there such an animal or has been Bubbarized?

[Doran]

Original finish military barrels are blue.

[Johnny Peppers]

Barrels taken out of pistols during rebuild that were serviceable were sandblasted and given a phosphate finish, and reused. The F mark ahead of the barrel lug came into use in the late 1943 time period around serial number 1,100,000.

[Mark Hitchcock]

Thanks Johnny, That solves my problem. The bore of this barrel is almost new.