By Robert G. Segel
Collectors, shooters and historians familiar with the Browning family of .30 caliber machine guns are generally intimately acquainted with the versatile M1917A1 tripod as used with the M1917A1 Browning water-cooled machine gun. Rock steady with integral traverse and elevation mechanism, it saw service from its adoption in 1935 through the Korean War. It’s only real drawback to the soldier in the field was its weight. But just as the M1917A1 Browning machine gun was an improvement of the M1917 Browning machine gun, so too was the M1917A1 tripod an improvement of the M1917 tripod.
Approximately 20,000 M1917 tripods were produced in 1917-1918 by two manufacturers: the Nelson Blower & Furnace Company of Boston, and the Crown Cork & Seal Company of Baltimore. The M1917 tripod was an improvement of a tripod originally designed and patented by John Browning for his early water-cooled guns that he built in 1901 and in 1910. The basic improvements were lightening the total weight by cutting spaces in the left and right tripod cradle side plates and refining the elevation mechanism. Unlike the later M1917A1 tripod that had a traverse and elevation mechanism incorporated as a single unit at the rear of the cradle, the M1917 only had an elevation adjustment at the rear operated by a large elevation hand wheel marked with graduations to correctly set the elevation of the gun. Traversing was by a different method whereas fine traversing was accomplished by a “slow motion” worm gear located within the cradle socket above and ahead of the rear leg clamp. Additionally, the M1917 Browning gun attaches directly to the M1917 tripod cradle, whereas a separate pintle is attached to the gun (either M1917 or M1917A1) that fits into a socket in the head of the M1917A1 tripod.
Because of the height of both tripods and due to the weight of pulling a loaded belt from ground level through the feedway, which seriously affected the operation of the gun, both the M1917 and the M1917A1 tripods had a bracket on the left side cradle plate that facilitated the attachment of a slotted wood ammunition box. This presented the belt close to the mouth of the feedway and provided ease of operation of the working parts of the gun as the feed pawl lever is directly attached to the recoiling bolt. Ordnance Captain S.C. Stanley best described the M1917 tripod by writing, “The Browning Machine Gun Tripod, Model of 1917, consists of four major parts; the legs, the socket, the pintle and the cradle. The legs are steel tubing having feet attached to one end and the serrated connections to the other. The socket is of manganese bronze and is the part to which the legs are assembled, in which the pintle revolves and in which the slow motion mechanism and stops are attached. The traversing clamp is also attached to the socket. The pintle is the center member of the tripod and carries the cradle clamp and traversing stop pin. The cradle is attached to the top of the pintle and is used to allow a quick elevation or depression of the gun. It carries at its rear end the elevating mechanism which allows a micrometer adjustment of the gun in elevation. It has a 360 degree free traverse graduated on an adjustable dial at 20 mil intervals for 6,400 mils; a clamping feature on the pintle similar to that used on the British (Vickers) Mark IV Tripod; a slow traversing worm mechanism graduated in 2 mil intervals and traversing stops adjustable to a single mil both having a quick throw off to allow for free traverse; an elevating mechanism of 125 mils capacity and graduated to 1 mil on an adjustable dial; a cradle construction on the pintle which allows a quick elevation or depression of 30 degrees each way with graduation marks at 12-1/2 mil intervals. The weight is approximately the same as the British (Vickers) Mark IV Tripod, that is, 50 pounds.”
Captain Stanley continues in a conclusion that, “This tripod was not originally designed for the slow motion mechanism, or for stops. Accordingly the slow motion and stops are not especially efficient, although they are very quick and positive in action. The tripods have been issued to troops and such reports as have been received show them to be highly satisfactory. No adverse criticism has been received except in regard to the stops and slow motion mechanism.”
M1917 Browning machine guns were upgraded and modified to A1 specifications in a rebuild program in the 1920s and ’30s and an original M1917 Browning machine gun that has not been modified and upgraded is exceptionally rare. So too, the M1917 tripods were also modified and upgraded to the A1 tripod specifications. This often consisted of removing the traversing worm gear adjustment wheel mechanism attached to the worm gear and replaced with a tear-shaped cover over the resulting hole. An original, as manufactured, M1917 tripod is an extremely rare collectable accessory.
This article first appeared in Small Arms Review V10N4 (January 2007) |