Interesting helmet find

[BEAR]

I would think this is a heat lot number?

That is true. The A1 was only made by McCord and it was only a short run (only six months), so assumption being what is, I would assume the heat lots would follow a sequential order. Doing some additional research, the numbers range from 1 to 24 with a letter code in addition.

I'm sure that if I'm off base on this assumption someone will come along and correct me. This can't possibly be as complicated as the M1 heat stamps and dates.

BEAR