....the end result was that a low-temperature (energy-efficient) zinc phosphating (Parkerizing) process, using strategic materials which the United Statesicon had ready access to, became the most common phosphating process used during World War II to protect American war materials such as firearms and planes from rust and corrosion."
O.K., with the above information in mind, we also know through Inland documents, that they were using Parco-Lubrite for their phosphate coating. Parco-Lubrite is a manganese phosphate coating. How does that fit in with the above statement?

There's no doubt in my mind that Winchester was using zinc phosphate on their receivers throughout production. Barrels appear to have a black oxide finish early and a zinc phosphate finish later. Winchester was even using zinc phosphate on, at least some, M-1 rifle production (see GCAicon Journal, vol 22, issue 2, pages 11-14). The finish on those two Garands match Winchester receiver finish.

Finish on carbines varied, depending on the prime contractor, the part, and the time period.
Information
Warning: This is a relatively older thread
This discussion is older than 360 days. Some information contained in it may no longer be current.