My first M1 Carbine

[painter777]

I wonder if the Recoil Plate is the early style, with the canted rear wall.
They don't have as positive a lock down as the latter straight wall ones, Thus the change-over.
Also have see some with grime under the plates lip, that needed to be cleaned away for positive lock down/tighter fit.
And ........... Some just wear out.

Hopefully it's a easy fix.

Cheers,
Charlie-painter777