chrome bore

[Curtton]

I was always under the impression it was after 1950 when they started using chrome barrels.

from my sticky:

D1. Barrel. Both barrels are threaded (no pin). The original barrel has non-chrome lined bore, to protect the bore from corrosive ammo and increase durability, it was switched to chrome lined sometime in 1951.

1a. Non-chrome lined bore. 1949 - part 1951. This barrel wore out faster and it would be replaced with a chromed lined barrel during refurbishing but only worn out barrel would be replaced.

1b. Chrome lined bore. Part of 1951 - 1956 . Chrome bore became the standard barrel on the assembly line.

 

[obiwanbonjovi]

all 49 and 50 are non chrome, some 51s are chrome some are not all later ones are chromed