RJ Stampings m1

[Graham9]

The only bit I've read about the 4 digit stamp is a the numbers are larger than the 3 digit numbers.
Never seen a 4 digit rjs.

[Jimir]

Here’s an example of a RJ Stampings four digit number.

[Tank Destroyer]

Here’s mine from the Chaplain helmet

[Tank Destroyer]

The stamp does not show up as large, was hard to zoom in close and keep in focus and the stamp in in the doom and not on the rim.

[Tank Destroyer]

Better picture, the 4 is faint.