Late War M1 Helmet McCord

[Twthmoses]

Just a little comparing to ”real” stainless steel, vs what I call carbon steel.
In my little pet project of registering Mccord shells and their characteristic, I found that a larger number of shells in the range 1122-1214 (many other ranges too) have these carbon steel rings, while 1214 to about 1265 overwhelming stainless. Then Carbon is back.

This is from a 1290A (which I just found) and a 926K shell.

[Sleepwalker]

Hi there,

Stainless steel is the umbrella term for a large group of over 120 types of steel that do not rust. This is also what they have in common: they don't rust.
Most of them are also not magnetic.

It should also be difficult or impossible to determine which steel it is exactly.