Please Id this one USC CO 18 New Guy Again

At that time, the Lewis would have been common in .30 caliber for air service. The US had very few MGs in inventory upon its entry into the war in 1917, most of which were obsolete, so US forces didn’t have many US-made MGs available to them during WWI for either air or ground service. Therefore, they had rely largely upon French MGs (and also French artillery and aircraft). MG production was started in the US, but the war ended before very many MGs made it across the Atlantic. The US version of the Lewis Gun was made by Savage, and had been manufactured here since before the US entered the war.

My late father-in-law was a WWI pilot (though the war ended before he made it to France) and his letters of that time indicated that all of his training experience was with the Lewis Gun (he wrote some fairly detailed letters home). I even have his instruction manual for the Lewis Gun, which is well-used and not in very good condition. Of course, many different MGs in other calibers were used on French, British, and German aircraft.

By the way, the air and ground versions of the Lewis Gun were mechanically the same, but the air version had no wooden buttstock or barrel radiator jacket, and used a larger-capacity magazine.

Published references have suggested that the comprehensive crimping of the primers in these cartridges was due a tendency of the Marlin aircraft gun to blown primers. Further, the Marlin being a fixed synchronized MG would have proven a more difficult challenge in jam clearing. This ammunition was also used in the flexibly-mounted Lewis guns used by observers in multi-seat planes. Jack

Many thanks photo above is what I have with the 18,thank you for all the info.I’m hooked great History,kinda a cool thing, its not like bringing a 6 foot clock home and having the wife roll her eyes. I can hide these in plan site for a while.

THe “Marlin gun” referred to is the 1914 updated version of John M. Browning’s Model 1895 “Potato Digger” gun which had been offered in various calibers over the years. The 1914 version added cooling fins to the barrel and shortened the arc of the flapper that transmits the energy of the gas tapped from the barrel at mid-point to work the action.

Not actually an ammunition-related item, the improved version of the Colt 1895 that was used for both aircraft and tanks during WWI was the Marlin (or Marlin-Rockwell) M1917 and M1918. The main modification made was the elimination of the swinging lever (potato digger) which was replaced with a linear operating system, as the swinging lever was not practical in the confined spaces of tanks and aircraft. From all accounts, this improvement was not nearly as simple an engineering project as it would seem to be. The old-style swinging lever version did see considerable action as a ground gun during WWI by several armies (but not the US Army), and was an “Official” MG of Canada during the early part of the war. It had a disturbing tendency to overheat quickly.

I have seen only one of the Marlin aircraft/tank guns, and that was in a museum in Cleveland in the mid-1960s. I got to play with it for a few minutes before a museum guard ran me off (it was out in the open where anyone could touch it, and there were no “Do Not Touch” signs around). It seemed to be in operable condition. I have read that the Marlin MG was used in French aircraft, and maybe by other countries. I don’t know how much use the Marlin got in US-made aircraft but there was only a small number of those that ever saw combat anyway. Undoubtedly it was used by US pilots flying a variety of foreign aircraft such as Spads and Nieuports.

The 1917 Marlin MG of which Dennis writes is the one I meant. It was a re-engineering of the original potato digger by Carl Swebilius of Marlin and replaced the Vickers as the standard fixed MG for US aircraft late in the war. While made in considerable numbers, its service life was brief, being replaced by the M1918M1 and M1919 Browning MGs after the war. Both these latter guns were lightened and synchronized high ROF developments of the M1917 water-cooled gun. Jack

New Guy

Here are 4 different Cal .30 cartridges with the ring crimp. This gives you something to look for. You are now a collector. Some big time collections started with just one cartridge. :)

The Marlin MG was supplied in large numbers to Britain in 1940 and I believe the British contract 30-06 was made with the ring crimp to accomodate these guns.

Evening Ray
Thank you for the photos, I spent two hours trying to figure out what some of these were,I’ve been buying Ammo Boxes to display in my shop when I get it ramped up toward 2013, now realize being a restoration guy , build some display cabinets for all these shells. That and seeing how I got into gunsmithing for extra money, I pretty much do Antique Restorations, and was asked to make gun stocks.Now applying for FFL, they tell me its still part of a gun so I need FFL if I charge for my work, well long story short I bought and started on a 1873 and a few others, so If I have to get FFL, I might as well do it all. Having alot of fun and gunsmithing is much easyier, then playing with Cuckoo clocks and I enjoy this more.

I would be interested in any reference you have to support that statement.

In 1940 all aircraft, weapons, munitions etc, supplied to the UK were purchased by the British Purchasing Commission from gold reserves. There was no Lend Lease at that date. I have not seen any contracts for large numbers of Marlin MGs in the records.

The Remington contract was placed on behalf of the Royal Air Force to provide both .30 and .50 ammunition for the Browning guns fitted to aircraft purchased in the US, early B-17s, Kittyhawks etc.


From “The Browning Machine Guns” Goldsmith, “aircraft guns (Marlins) as well as some surviving tank guns (Marlins) were shipped to England in 1940”.

It’s inconceivable to me that even in the precarious position the RAF was in in 1940-41 it would have considered using the guns on aircraft. My impression is that Britain’s supply of .303 Brownings was pretty good by this time, and the problems with appropriate links for the feed system alone would have been considerable. The Marlins, particularly the more numerous aircraft guns, would have had little utility as ground guns because of their lack of a cooling system. Surely the U.S. army emptied some warehouse of everything and sent it to England, hoping it might prove of some use. Jack

Orange - thanks for the reference. I will chase it up with Dolf, but I have never seen a Marlin with British military inspection marks (that is not to say they don’t exist). Any Marlins that did come to the UK would probably have been issued to the Home Guard anyway.

Jack - I agree. As I said, the British contract with Remington was for the .30 and .50 calibre Brownimng guns fitted to aircraft we purchased in the US. It was not a case of the US army “sending” things to the UK at that time as it was prior to the Lend Lease Act.

I am giving a talk at SLICS on the British ammunition purchases in the US prior to Lend Lease.


“Military Small Arms of the 20th Century” states that the Marlins were fitted to UK merchant vessels as AA guns.
The above Browning books also list 82 M1914 colts bought by Britain in 1940, last of Colt’s inventory.

If I couldn’t get something better, I’d be happy enough with a Potato Digger as it’s far superior to throwing rocks at the Jerrys. I imagine that was the situation in 1940 Great Britain, especially after Dunkirk. I remember the tales about rounding up about anything that could shoot in the US, even civilian weapons, for shipment to Britain at this time. At least it was a morale booster if nothing else.

I also have this one with the 1940 date.

My apologies Orange, but with the help of my good friend Alan David I have found the details of the Marlins supplied to the UK.

In mitigation, I would plead that I had checked the Home Guard weapon returns and there were no Marlins shown, but it turns out they are simply listed a “.300 inch machine guns”. It seems that some 1,500 guns went to the Ministry of Aircraft Production to defend factories where they were set up in quad mounts. Others were dropped to the French resistance by the SOE.

It seems none were marked with British inspection stamps.


As there has been previous mention above of the Marlin-Rockwell MG use by Great Britain in WWII, this is a site showing a manual about the quad-mount Marlin-Rockwell MG in .30-'06, as used for homeland anti-aircraft defense. Very ungainly, but if you are being strafed by Messerschmidts, you might have stood a small chance of hitting one. … Manual.pdf

By the way, is a fairly interesting site to visit with many photos of interest.

HWS Vol1 states that the heavy ring crimp on 30-06 ammo was to prevent blown primers in the Marlin MG. The introduction of this obsolescent arm into British service would explain the presence of this crimp which had gone out of use 20 years before 1940 on British contract ammo.

It’s worth noting that an illustration in HWS v. 1 shows a .30 caliber cartridge from one of the U.S. government’s educational contracts with commercial firms in the U.S. in the late 1920s with this same heavy annular crimp. The round is headstamped RA 27. So, evidently, the crimp did not go away between 1919 and 1940. Jack