Receiver Proof Marking

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   FWIW, I remember - about 40 years ago - Larry Ruth told me that Rochester, NY area gun shows (where he lived and where NPM was located) had plenty of unused NPM parts on dealers' tables, including receivers that had walked out the door.  That was when I first heard the term "lunchbox special."

Regards, mb

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Marty Black Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Editor in Chief Emeritus Joined: Dec 30 2015 Location: Pismo Beach, CA Status: Offline Points: 100542	Post Options Post Reply Quote Marty Black Report Post Thanks(0) Quote Reply Posted: Mar 07 2025 at 12:35pm
	FWIW, I remember - about 40 years ago - Larry Ruth told me that Rochester, NY area gun shows (where he lived and where NPM was located) had plenty of unused NPM parts on dealers' tables, including receivers that had walked out the door. That was when I first heard the term "lunchbox special." Regards, mb
	Marty Black

jackp1028 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Jan 01 2016 Location: Cloudcroft, NM Status: Offline Points: 1450	Post Options Post Reply Quote jackp1028 Report Post Thanks(0) Quote Reply Posted: Mar 20 2025 at 3:10pm
	I noticed that the Inland bolt without a proof punch mark that I mentioned in an earlier post on this thread also has an "X" stamped on the right lug. Any ideas what this means? Here are a couple of pictures.
	JackP

Marty Black Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Editor in Chief Emeritus Joined: Dec 30 2015 Location: Pismo Beach, CA Status: Offline Points: 100542	Post Options Post Reply Quote Marty Black Report Post Thanks(0) Quote Reply Posted: Mar 20 2025 at 3:33pm
	This was discussed by Brian Quick in NL 370-8. There is documentation that an X stamped atop a round bolt by IBM and Quality Hardware indicated that that particular bolt did not have all the design revisions incorporated for the round bolt. An X stamped on the right lug of an Inland bolt is likely something else, because the X-marked bolts that were examined had all the design changes incorporated. These Inland bolts (several) were in the 5.1 - 5.5 million range, and one bolt at 6.4 million. Research by Brian Quick. Regards, mb
	Marty Black

New2brass Members Profile Send Private Message Find Members Posts Add to Buddy List Moderator Group Dan Pinto, How Can I help Joined: Nov 29 2015 Location: CCC Status: Offline Points: 5527	Post Options Post Reply Quote New2brass Report Post Thanks(0) Quote Reply Posted: Mar 20 2025 at 4:35pm
	There is an Inland COM with one of those bolts
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jackp1028 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Jan 01 2016 Location: Cloudcroft, NM Status: Offline Points: 1450	Post Options Post Reply Quote jackp1028 Report Post Thanks(0) Quote Reply Posted: Mar 20 2025 at 5:46pm
	COM 372 (6.4M Inland) has "X" marked lug. Unable to tell if it was proof marked.
	JackP

painter777 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 18 2016 Location: Central MI Status: Offline Points: 2352	Post Options Post Reply Quote painter777 Report Post Thanks(0) Quote Reply Posted: Apr 12 2025 at 4:51pm
	JP, JD, passed along a auction link to a EMB Round Bolt that appears to show no Proof Punch Mark Ebay Auction number 197008706149 Thx JD, Ch-P777
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GeorgeE Members Profile Send Private Message Find Members Posts Add to Buddy List Recruit Joined: Feb 08 2025 Location: Ohio Status: Offline Points: 2	Post Options Post Reply Quote GeorgeE Report Post Thanks(1) Quote Reply Posted: Apr 12 2025 at 6:45pm
	I have what I believe to be an original 2.2mm Standard Products that has no punch mark on the receiver, just the bolt. Barrel is an Underwood with a normal proof "P". Guess they could be missed.

MilsurpsUSGI Members Profile Send Private Message Find Members Posts Add to Buddy List Recruit Joined: Jan 01 2016 Location: OR Status: Offline Points: 27	Post Options Post Reply Quote MilsurpsUSGI Report Post Thanks(1) Quote Reply Posted: Apr 12 2025 at 8:06pm
	Painter, Here's a picture of your N-14 cracked bolt. You got another N-14 from me that has a similar group of "peck" marks behind the extractor. Not sure if they are supposed to be the "proof" mark or a result of hardness testing. I've read of the reported failures on these, and it does look like there could be a link as some have suggested. Just found a picture of the one I sent you, so will attach it also. - Bob

painter777 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 18 2016 Location: Central MI Status: Offline Points: 2352	Post Options Post Reply Quote painter777 Report Post Thanks(0) Quote Reply Posted: Apr 12 2025 at 10:29pm
	Hello GI Bob, It was you that pointed out the rough wear marks with vertical lines behind the Left Lug after it broke the Right Lug on me. That Wear can be seen in my replies near the end on page 2 here: http://www.uscarbinecal30.com/forum/anyone-seen-a-m1-carbine-bolt-get-shattered_topic3154_post63222.html?KW=#63222 It was also by looking at the cracked bolt in the receiver that I noticed that the 0 in .30 was broken, looking like a backward C, So I reported that. I'd never noticed before. You'll read in the Link that I polished around the locking left shoulder and NOW make sure I grease on the pad and behind it, to prevent any binding. I'm still using the Bolt I got from you and shoot that NPM on most trips. I reported to JP that it also has a very light Punch. It was JP - Jack that started the inquiry about some Receivers and Bolts being found without the Firing Proof Punch Marks. In your last added picture of my current Bolt, on top of the right lug would be the hardness pr!cks. From what I've seen so far, NPM have the smallest marks followed by Stan Pro. I'll continue to look. Will you be getting the bed back on and Waxing my Truck soon? Thx Buddy Charlie-P777 PS: Did my Check clear for that Bolt?
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painter777 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 18 2016 Location: Central MI Status: Offline Points: 2352	Post Options Post Reply Quote painter777 Report Post Thanks(0) Quote Reply Posted: Apr 14 2025 at 1:57pm
	@JackP, USGI Bob posted a picture of a EMQ Flat Bolt he put in one of his Inlands that we can't see any Punch Mark on. It's over on Milsurps. Reply #7 https://www.milsurps.com/showthread.php?t=81076 Ch-P777
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Jond41403 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 21 2021 Location: East Tennessee Status: Offline Points: 874	Post Options Post Reply Quote Jond41403 Report Post Thanks(0) Quote Reply Posted: Apr 14 2025 at 2:32pm
	Good to see you on here Bob!

jackp1028 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Jan 01 2016 Location: Cloudcroft, NM Status: Offline Points: 1450	Post Options Post Reply Quote jackp1028 Report Post Thanks(1) Quote Reply Posted: Apr 14 2025 at 6:54pm
	@Charlie, thanks for the input. It looks like missing proof marks on bolts is not that unusual. So far, I've seen examples of NPM, IBM, Underwood, Inland, QHMC and Standard Products bolts without punch marks. The NPM bolts that do have proof marks are almost always very lightly punched. It would be interesting to see what your damaged bolt measures on a Rockwell C hardness tester. I'll check around my little village to see if there is a shop that has a hardness tester. Perhaps you can do the same. Maybe we might be able to see some actual objective evidence of difference in hardness between NPM and, say Inland. The specification is Rockwell C38-C43 at the lug and Rockwell C48-C54 at the rear per the Army Ordnance specification. Any harder and they might be brittle.
	JackP

Smokpole Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Oct 21 2019 Location: Madison ohio Status: Offline Points: 1484	Post Options Post Reply Quote Smokpole Report Post Thanks(0) Quote Reply Posted: Apr 14 2025 at 7:29pm
	I looked at the receiver of my IP yesterday. There was only a single punch mark.
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Jond41403 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 21 2021 Location: East Tennessee Status: Offline Points: 874	Post Options Post Reply Quote Jond41403 Report Post Thanks(0) Quote Reply Posted: Apr 14 2025 at 9:06pm
	since N14 marked bolts are wartime bolts, wouldn't it have shown itself during the war if they were too brittle or too hard? Seems like if there was a problem with that specific marked bolt, It would have been discovered back then. Or who knows maybe it was discovered back then and we are just rediscovering something that was already known during the war. I just can't wrap my head around if those bolts are defective, it should have been obvious back when they were being used during hard conditions

Jond41403 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 21 2021 Location: East Tennessee Status: Offline Points: 874	Post Options Post Reply Quote Jond41403 Report Post Thanks(0) Quote Reply Posted: Apr 15 2025 at 3:10pm
	It makes me also wonder if there were ever any documentation discovered by anybody in the club pertaining to recalled carbine parts during the war. I know I P had a bunch of documented out of spec parts but I wonder if there was ever a recall of anything from the other makers? That's what these marks are all about is in case something goes wrong they can trace it back to its source, I just wonder if there's any documentation of any recalls during the war or even after

painter777 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Feb 18 2016 Location: Central MI Status: Offline Points: 2352	Post Options Post Reply Quote painter777 Report Post Thanks(0) Quote Reply Posted: Apr 15 2025 at 5:20pm
	Seems we covered N14 Bolts pretty well in the Post I'll link below. We've found plenty of other maker Bolts that give way. You think it's a case of N14 just being stuck in our heads? Now in the Link Manteo97 had a busted N14 being sent to him by fellow member carbinecanuck that he was going to do a hardness test on, but I can't find any follow up about it. Manteo97 does mention: "A quick review of past CCNL's indicates N14 marked flat bolts were used from Dec '43 to Feb '44 or later based on barrel dates, and other data. This would be roughly 4.1 mil S/N range and higher. NPM made these bolts in-house, apparently the number (8, 9, 11, and 14) indicate drawing and/or design changes. Union Switch & Signal also made UN marked bolts under contract, and these are found towards the later part of production. So, that kind of indicates maybe 150,000 or more M1 carbines came out of the NPM factory with N14 bolts." Would assume there would have been extra N14's made, but no idea of how many total in issued Carbines plus Extras. Likely not a huge margin of the 150,000 if manteo97's numbers are on. Someone correct me if I'm wrong but I believe it was NPM Flat Bolts that Did Not have all the upgraded design changes. Maybe this could be one of the factors in the Bolt breakage? Link: http://www.uscarbinecal30.com/forum/anyone-seen-a-m1-carbine-bolt-get-shattered_topic3154_post20349.html?KW=#20349 @JackP, I'll look around for a place to test my bolt. But I need time, I'm currently caretaking the Wife who broke her knee cap in a trip. Thx for the Specs. Ch-P777
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jackp1028 Members Profile Send Private Message Find Members Posts Add to Buddy List Hard Corps Joined: Jan 01 2016 Location: Cloudcroft, NM Status: Offline Points: 1450	Post Options Post Reply Quote jackp1028 Report Post Thanks(1) Quote Reply Posted: Apr 18 2025 at 3:32pm
	@Charlie, I struck out finding a local shop that has a hardness tester. The only shop within fifty miles uses a file to judge hardness. I can do that. None of my bolts are more than Rockwell C60 (the hardness of my die file, I think). Yeah, I know, not much help. Maybe you will have better luck.
	JackP