Midway carbines

[Ben Cartwright]

I am just learning about M1's here is my Quality Hardware (VG-F) box came through fine, no dents or tears. Seems to be in very nice shape, just a tad of cosmoline under the top handguard and in it.
Serial # 156XXXX
Quality Hardware under adjustable sight
ROCK-OLA barrel dated 2-43
Top handguard marked OI
Stock only marking I could find is a "V" in the receiver well
Square cross hatch on recoil plate
"L" on Trigger group
flat bolt
UI on the barrel band - Type 1

what is the "V" in the receiver well?