WWI 45 ACP for Revolvers

I have a 45 ACP with the headstamp of REM-UMC 18 and the three stab crimps on the neck and a bunch of questions.

  1. Are there any other headstamps for 45 ACP with stab crimps?

  2. Was the stab crimped ammo only supplied on half moon clips, or is it also found in regular 20 or 50 round factory boxes? Any commercial boxes with stab crimps?

  3. Was any non-stab crimped 45 ACP packaged on half moon clips?

  4. Other than taking an original set of three rounds and their clip out of a sealed box, is there any way to tell original GI half moon clips from later civilian production clips?

  5. Was any 45 ACP packaged on half moon clips during the WWII?


Curt - I can only give you partial answers, but I will try my best. I don’t collect dates in .45, with a few special exceptions, so will say right off that all my rounds with revolver crimps that are dated, including those in the three sample boxes I have, are from 1918. That does not mean that none were made in 1917. I simply don’t know. Also, every round I have in my U.S. .45 collection, that has stab crimps, is with a tinned, FMJ RN bullet. I have not included any foreign rounds (as I recall, the Brits stab-crimped some .45s, and perhaps others) because it seemed outside of the scope of your questions.

Your questions:

  1. Yes. I have P.C.CO 18 and U.S.C. CO. 18 in my own collection, along with the REM-UMC 18. Neither Winchester nor Frankford Arsenal seem to have made any with the stab neck crimps, but that is only based on my own collection. Neither did Maxim.

  2. I have not seen any “20” or “50” round boxes with ammo on clips. Because a clip holds three rounds, those boxes, if the existed, would have to be either for 18 or 21 rounds, or 48 or 51 rounds. They could not be for 20 or 50 rounds even. I have never seen any box other than 24 rounds, of which there are two styles at least in Remington. I don’t have a box from Peters, unfortunately, but I do have a shorter, wider style box from Remington dated February 2, 1918, a longer, narrower style box from Remington, undated but with “18” dated ammo, and a long, narrow box from U.S.C.CO. dated SAugust 16, 1918. I have never seen a commercial box where the ammo could be identified from the label as “Revolver Only” or as having stab-type neck crimps. I have not seen any such ammo come out of a box, but I think one at least must exist - see below.

  3. I have never seen any 24-round box with ammunition in it NOT having the stab crimps. Again, doesn’t mean they don’t exist. I just have not seen one, and have been collecting .45 ammo for 52 years.

  4. This is a yes and no question, both at the same time. There have been commercial clips exact copies of the G.I. including being blued, clips the exact same shape be not blued, and clips of different shapes including some for two rounds, three rounds and six rounds. The short answer is that you cannot positively identify the clips as G.I. or not without some documentation (provenance, box label, etc.) other than the clip itself. That is simply my opinion. I would welcome be found wrong if someone has a way to tell.

  5. I have never seen a WWII-vintage box for .45 ammunition packed in half-moon clips. The only WWII-era boxes I have in my own collection which are “Revolver Specific” is are both for the M9 blank. One is from Evansville Ordnance Plant, with box overstamped in purple stamp-pad ink “For use in revolvers only.” The other is from Frankford Arsenal, Lot FA 2, with the label printed REVOLVER BLANK, CAL…45 M9 (T1-E2). Both are steel-case and both are dated from 1944 with the single “4” date.

  6. This number added by JLM. I have in my own collection one commercially-headstamped PETERS .45 A.C. I believe this to be a commercial round only, as it has a 200 grain bullet along with the proper height case cannelure for that date. I have not seen the box it was in originally. I believe this may be simply one lot of ammo that failed the crimping or bullet-release tests, and therefore had the crimping reinforced by stab crimps. Just a theory. It could have been for revolvers as well. After WWII, the U.S. Post Office had many of the 1917 revolvers, enough so that there is even a holster with the Post Office insignia (an oval, but I don’t recall what it said) insteal of the “U.S.” in an oval. I believe the PO holsters were “butt to the rear” unlike the military, that were cavalry-style “butt forward” but I could be wrong. It has been a long time since I have seen one and I never owned one. I recall as a boy in grammar school in the mid-to-late 1940s that all of the drivers on the Postal trucks that picked up mail from the boxes were armed, in our area with these 1917-revolvers. Yes, I was a “gun nut” even as a pre-high school child, and noticed these things and pestered the people wearing guns. I didn’t pester the cops, because in San Francisco in the day, they wore their guns under long coats!

That’s about all I can say addressing your subject. Sorry I don’t have more definitive answers. One of the problems of not date collecting and being limited most of my life in the boxes I could afford to buy.

HWS I, page 24, has a one paragraph entry regarding the 3-stab crimp. It indicates that the crimp was standardized in Jan, 1918.


As usual, your answers exceeded my expectations. Thank You. You have provided some new leads for me to run down. I may not have been clear on Question 2. I should have made it clear that I was asking about 45ACP that was stab crimped but never packed on clips and packaged in regular boxes. I think your answer to Question 6 may have answered my question from a different angle.

With the information that John has provided I can correct my nomenclature. Since the clips were produced by commercial entities and never at the government arsenals, it may be hard to classify them strictly as “GI”. So now I will call the original WWI production clips or 1918 production clips as to distinguish them from commercial production at various times in the last 96 years. I was concerned about displaying three WWI era rounds in a clip of visibly modern manufacture. It would appear that any variations in the clips from different times and different manufactures are very minor. I really can’t say that without trying to compare and document half moon clips of known manufacture. I may have found a new quest!

Here is a new question:
During WWI, were the half moon clips manufacture at each company that loaded the stab crimp ammo or were they made by one company (perhaps Smith and Wesson?) and distributed to the others?



The half moon clips, which were made for use in the S&W Model of 1917 and Colt Model of 1917 .45 ACP revolvers, were invented by D.B. Wesson of Smith & Wesson in 1917. S&W manufactured these half moon clips in WW1. I don’t know if anyone else made the clips during WW1 but to do so would probably have required a license from S&W. S&W did not manufacture ammunition during WW1. I believe that it supplied the clips in bulk to the ammunition makers who assembled and packaged them with the ammunition.

The photo below, taken from Hayes Otoupalik’s site, shows a 24 round box of this stuff as made by Remington UMC.


Charlie, the half-moon clips was in fact patented in 1918 (application filled August 15, 1917) by Joseph H. Wesson, one of Daniel B. Wesson’s sons, who also designed a machine to load them. He also designed various full-moon clips and even a quick loading carrier for 24 cartridges.

Why were “half moon” clips produced in the first place? Meaning, what is the advantage of “half moon” vs “full moon” design? Half moon requires 2 clip load vs 1 item load for full moon. What happens if you drop one half moon in the mud? Sounds like “full moon” is a better idea. Also, is “clip” a proper name? They are not “chargers”, could they be “magazines”?

I am guessing that full moon clips were not done, because no one thought to make them at that time?

Ref the boxes of full moon clips - I have seen, but not bought a couple of boxes at Allentown - kept meaning to buy one over the years and now I have moved away.

John, ref the holster - I seem to recall a picture that had the oval and USPS on it, but I could be mis-remembering.


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I would speculate that “full moon” clips were not made so as to reduce ammunition wastage when reloading between engagements. With a “full moon” its all or nothing, even if you fired only 1 round. A half moon would be better inorder to keep a fully-loaded cylinder in the weapon.

Just my thoughts.


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Also not as bulky & probably easier and faster to unload & reload the clips.

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In using a full moon, versus half moon in my model 25-2 - full moon clips are incredibly easier and better to use. They slide in easier and easier to keep track of.
If I was in war time, and used three of the 6, I would pocket it and throw in another full clip. If they had them.

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Also, the Halfmoon clip was flatter and easier to make a 24 round Leather/ Canvas Pouch for.
Hence a 24 round Packet ( 8 half Moons, 4 full revolver loads.

The only other type of Quick reloader of the time was Webley’s
Commercial 6 round charger for the Webley revolvers ( .455 and .380)… only used by private purchase in WWI.
Doc Av

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Also, not to forget that the half-moon clip was an “adaptor” al least as much as a storage or loading “clip” … in that it allowed the easy and quick extraction of fired unrimmed cartridges from a revolver’s chamber by giving the extractor something to bear against.

Another example of John Moss’s insistence that cartridge, “chargers” and guns be thought of as a piece, each essential to make a viable operating tool, you can have one without the others … but it’ll be a lot less useful to you.


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