NO Receiver or Bolt Proof Firing Punch Mark Search

[painter777]

Looking for M1 Carbines and Bolts that are Missing the Punch or Pr!ck mark on them that means they went thru a Proof Firing test before Ordnance acceptance.
The Receiver, Barrel and Bolt are to be marked by the Ordnance Inspector to indicate that they have successfully passed the Proof Firing test with a high pressure M18 proof cartridge. This applies to finished carbines, spare bolts and spare barrels.

Not to be confused with the Rockwell Hardness test smaller pin pr!cks.

A long time member has found: "I have a US&S NPM (U) receiver and a late WRA receiver without proof marks. Both appear to have the original finish. Both appear to have little to no wear from typical use. I also have NPM, Inland and Underwood bolts without proof marks."

Anyone else have a Receiver or Bolt with NO Proof Punch?

To All: Any thoughts to Why no such marking?

Thx For Looking

Bolt and Receiver Proof Firing Punch Pictured