CM marked bullet guides

[604flyer]

Does anybody know what the CM marking on WRA bullet guides stands for? TIA

Information

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[Bodyman]

Lots of chromium and moybdenum in there and supposedly required a slightly different finishing procedure so they had to mark the individual parts to keep track. A marks denote another type of steel, as well (the details must wait for Bruce Canfield's new book there!), but what gets me is the double marked ones with both A and CM ...

[Redleg]

I do not find references to chrome moly experiments at Winchesters leisure, in Hatchers Notebook or his Book of the Garand.

Winchester followed the contract exactly, causing many little headaches and did not revise the receiver version from "-2" till 1945. they were not paid to change it, so did not. Same thing on many parts.

Chrome moly is generally in the 4000 steel range.
That steel is not up to the required "WD8000" steel series standards-- (War Dept for WD) after the "diamond change" and not referred to in the earlier mixes at all. I also refer the reader to the Kuhnhausen book and the Pyle book.

Op rods were a mix of two parts and two steels, but no chrome moly. Gas cylinders were a SS blend. All parts had specified steels that were used.
That is fact, and no messing around.

I believe that the long held idea that "CM" was just a reference to a local manufacturer or subcontractor is still substantially correct.

Winchester would NOT experiment, could not experiment or be ALLOWED to experiment with ANYTHING in metal composition outside of specs-- due to the specified contract costs and specific materials being specified in detail.

For Winchester and their reputation to go way out on a limb and say "hey we gotz some time and lets try some new plastic copper nickle wizbang new process to stick in those them there Garands"--- it is ludicrous to consider it in war time, with all the inspectors and Art Tuttle and John Garand so close by.
I can almost guarantee that CM would not refer to any different steel or extra process, secretly done by Winchester, any more than "A" refers to the human posterior.

[Ramboueille]

I do not find references to chrome moly experiments at Winchesters leisure, in Hatchers Notebook or his Book of the Garand.

Winchester followed the contract exactly, causing many little headaches and did not revise the receiver version from "-2" till 1945. they were not paid to change it, so did not. Same thing on many parts.

Chrome moly is generally in the 4000 steel range.
That steel is not up to the required "WD8000" steel series standards-- (War Dept for WD) after the "diamond change" and not referred to in the earlier mixes at all. I also refer the reader to the Kuhnhausen book and the Pyle book.

Op rods were a mix of two parts and two steels, but no chrome moly. Gas cylinders were a SS blend. All parts had specified steels that were used.
That is fact, and no messing around.

I believe that the long held idea that "CM" was just a reference to a local manufacturer or subcontractor is still substantially correct.
Winchester would NOT experiment, could not experiment or be ALLOWED to experiment with ANYTHING in metal composition outside of specs-- due to the specified contract costs and specific materials being specified in detail.

For Winchester and their reputation to go way out on a limb and say "hey we gotz some time and lets try some new plastic copper nickle wizbang new process to stick in those them there Garands"--- it is ludicrous to consider it in war time, with all the inspectors and Art Tuttle and John Garand so close by.
I can almost guarantee that CM would not refer to any different steel or extra process, secretly done by Winchester, any more than "A" refers to the human posterior.

Redleg,

You need your research updated. GCA Journal , Winter 2006, the CM mark has been solved (it's Chrome-Moly steel) 5 years ago. And "A" marked WRA parts has also been solved by Bruce Canfield, GCA Journal, Fall 2010. It's also another steel type that WRA tested and used. There's no secrets about either anymore.

[cgroc09]

What about the parts that were stamped with an "A" and "CM" ?

[Ramboueille]

What about the parts that were stamped with an "A" and "CM" ?

For the same reason this happened: Human error

[Bob Seijas]

It's pretty clear that if you don't want to spend the 25 bucks for a GCA membership, you will not be up to date on the latest Garand discoveries. The CM was nailed by Tony Pucci in chemical analysis and later confirmed by Bruce Canfield from the private memos of the head of WRA. Nobody who has read those two articles would advance theoretical guesswork on the subject, it is proven and closed.

[Redleg]

With all due respect, the argument rings hollow. It does not seem to be credible, whatsoever.

I could believe that during the years from 1930-40 that John Garand may have experimented and changed metallurgy for failing components, based upon user experience and wear patterns.

I find it simply beyond the pale that Winchester had any lattitude at all in deciding what sort of metal to use, other than what was mandated. They changed nothing unless paid.

To suggest that they did what they wanted seems to be contradictory and without foundation or support from SA.

Anecdotally, gunsmiths like G fisher would have noted some sort of pattern over the years with those CM marked items; that has not shown to be true.
I suspect that in fact there is no deviation at all in metallurgy between CM, A, and punchmarked and SA items.

Only a test of all types of bullet guides, clip latches, trigger housings etc of all of them would show such a claim to be true.
That has not been done.

In any sort of scientific method there is a way to prove things and "one" does not make a trend or a truth.

The list of metals used is available in any of the above mentioned books.

Do you have a link?

[Bodyman]

For the same reason this happened: Human error

That, and WRA's dislike for the design but the ability of that robust design to handle such things. About the only thing I ever thought about the double marked parts was that they pretty much disproved the subcontractor ideas on CM and A marked parts.

There are also double marked parts with 2 CM's, CM's with dashes, several sizes and fonts of A's and CM's ...

This one still makes me scratch my head though ...



(hee hee hee) ...

PS; I am pretty sure I was the one who noticed this particular double marking on the trigger housing when I got to handle this rifle in person.



I LOVED that rifle. Scott had just gotten it in, and hadn't really gone over it with a fine toothed comb yet - I took out the trigger housing and low and behold, there it was! "You seen this yet?", I asked. "Well, would ya look at that ...", he replied.

I have only ever seen one other trigger guard like it for sale, loose, and it went for a really tidy sum. Oddly, both of them were offest like this so they can be read ... like somebody wanted them both to be read. But WRA never put the same effort into markings like SA and dots and dashes just don't quite have the same weight. Drove the SA guys crazy, but the WRA guys really wanted to know how it helped them on originality ... that and the use of Chrysler's Amola is really quite a story.

[Ramboueille]

Only a test of all types of bullet guides, clip latches, trigger housings etc of all of them would show such a claim to be true.
That has not been done.

Do you have a link?

That was done, a metallurgical laboratory conducted sceleroscope tests of various A marked, CM marked and unmarked WRA parts and the test showed conclusively CM marked items contained a large percentage of Chrome-Moly steel across the board. The others did not. How can you refute what you have not seen or read? It's proven metallurgically and in the WRA archive records. It's one thing to be in denial but quite another to refute valid based metallugical sceleroscope tests and WRA Archive records that state specifically what you are denying. What more do you want?

A link for what? The articles? Yes:

http://www.thegca.org/pdfs/back_issue_order_form.pdf

Winter 2006

Fall 2010