NPM carbine help ..

[imntxs554]

Thank You Bob, That answers part of my question...ALL receivers had a Proof (Punch) mark. Then now I can look at just the Barrels to see if ALL had them also.

In 2010 there seems to be the same discussion if NPM did use 2 type of Proof Marks. There's some same type of questions and answers and pictures of 3 different Barrels on NPM Carbines placed there other Punch Mark.

https://www.milsurps.com/showthread....267#post124267


Frank

[tenOC]

Here's a couple pictures of an NPM that show somewhat similar stake marks. I've never seen a carbine that didn't have the "proof test" punch mark on the receiver. It was required for acceptance by the government. Those never accepted such as presentation carbines wouldn't necessarily have been required to have undergone proof testing with a high pressure round. - Bob

Saving both images down, the staking doesn't look the same to me. NPM is known for skinny chisel staking and at least two of my NPMs have long sharp chisel staking, but the OP's appears to be fatter as well as longer than any I've seen. Like a blunted object made the one forward especially. Would like to see closer images of the right side in good lighting. Not saying it's not original. As we know there are oddities, which makes this more enjoyable.

The high pressure round is what I understand the mark is. The only Carbine I've ever had without it was probably scrubbed off for a refinish. Here's the link.
Punch mark for hardness proofing. - CMP Forums

[imntxs554]

This NPM was lucky to not have Stake Marks, if it did I'd rather it look like some I've seen that are small. I still think it was done twice. IMO ! Who really knows. I wonder if it gets described in the CCNL'S and maybe they can look them up on the description of how they look, but I assume it will just say "Has Stake Marks".

[tenOC]

Do any of the publications show the devices used by the different manufacturers to stake receivers?

[johnboy]

Hi, Mr. Robert Eakins of the carbine forum has found a national postal meter with the same type of hammer LTQ in a data sheet, I believe it was in the 409xxxx range, so some hammers were transfer or receive from Quaility Hardware, still have not found the barrel band as of yet,