The lesser known Lewis designs.
Isaac Newton Lewis is most famous for his successful Lewis machine gun of 1911, a weapon used extensively in WWI and still occasionally seen all the way through Korea. This gas (piston) powered rifle had a few quirks, the drum magazine advancing system and the main action spring being notable. Interestingly, the design originally came with a large cooling shroud covering the barrel, but these were often seen as unnecessary and removed.
However, hardly anyone seems to remember his later, highly unique intermediate designs. With patents filed from 1918-19 and granted in 1922, his “Shock Action” system for both “light” infantry rifles and pistols is worth inspecting.
At heart the design utilizes a modified type of gas-trap system, one where a portion of the gas released by the muzzle blast enters and fills (or otherwise produces force within) a large casing almost entirely encapsulating the barrel (rather than simply a small cavity). This gas, or hopefully as is described in the patent, a “shock-wave” is sent bouncing backward after crashing against the end of the barrel casing shroud, exerting pressure upon a tubular piston (in the above rifle patent drawing, part 13, with the pistol, 55) “in the form of an annular disc which is slidably mounted upon the barrel” and filling the gap between the barrel and outer “casing” or shroud wall. This barrel-mounted tube piston is connected to a traditional solid piston rod housed above the barrel, which acts upon the bolt in a more or less standard fashion.
US Patent 1430661 explains the benefit of this system in these terms: “An important distinction must be drawn at the outset between the present automatic… firearm operated by shocks or pressure impulses, and firearms operated by the direct pressure of the heated gases of discharge upon parts connected with the actuating mechanism of the firearm. In the improved firearm the hot gases of discharge do not necessarily come into direct contact with the actuating mechanism… and preferably are transmitted to said mechanism… through the medium of an intervening column of air. Thus said mechanism, or said parts, do not become highly heated by the gases and do not become fouled by deposits therefrom, enabling the firearm to be operated for more extended periods without cleaning, and preventing jamming or inefficient operation due to said fouling deposits.” In addition, the patents explain, recoil is reduced and the overall mechanism forces air over the barrel and internal mechanism while firing, helping to further cool the weapon.
Contemporary and later true gas trap designs, such as the Bang M1922 and the early Garands, gained a reputation for being finicky, owing mostly to excessive fouling. Lewis’ system seemed to have included most of the beneficial aspects of the traditional gas trap rifles (the Germans felt gas trap guns were more accurate, also they were theoretically more forgiving of a variety of bullet weights, powder loads etc.) and additionally may have avoided the issue of excessive fouling. I haven’t been able to find any documentation detailing why exactly this design never went anywhere. Likely it was just seen as too complicated and costly as weighed against the potential benefits.
- The top photo is the only one I know of depicting an assembled prototype of the rifle described in these patents, and was generously supplied by ForgottenWeapons.com (taken at the National Firearms Center in Leeds).
- Below that is an image from Great Briton patent 177550A, which is more straightforward than the US patent drawings. It is interesting to note that in these patents the rifle is shown to include “a metallic member or plate (US 143, GB 5) which may serve not only as a firing mount or support for the gun by resting the lower part thereof against the ground or other object, but which also serves as a shield or protector for the head or body of the gunner when firing the gun.”
- Below that is a photo of a fascinating example of the shock-action system having (presumably) been applied by Lewis to a rotating bolt, locked breech .45acp pistol design! That Lewis was able to convince anyone (even the company bearing his name) to machine and assemble a working prototype of this bizarre, complicated handgun seems to me a wondrous thing. The built example does outwardly deviate enough from the patent drawing to cause a suspicion that it may indeed be a simpler, derivative design.
- To the right is an image from the pistol patent US 1430662.
- Below that is a much more commonly available image of what appears to be a later transitional model rifle with a full-length, perforated handguard. It looks to me as though it’s outfitted with a true gas-trap mechanism integrated into the sight block at the front.
- The bottom image is of a later “Lewis M1924”, a detachable box magazine machine gun sporting a run-of-the-mill looking gas-piston system (this rifle was probably built by the St. Denis factory of Lewis Guns but may or may not have actually been based on a patented design by Isaac Lewis). Apparently these are all treated in William M. Easterly’s book The Belgian Rattlesnake, although I have never read a copy.
On a personal note, this is one of the earliest strange gun designs to catch my eye and cause me to become interested in obscure weapon systems when I was younger, so it holds a special place in my heart.