The Browning medium machine gun (.300 inch, Model 1917) is an automatic weapon firing small arms caliber .300-inch ammunition, the gun being mounted on a tripod so that the direction and elevation of fire may be arbitrarily fixed by the gunner by means of the elevating and traversing mechanism incorporated in the tripod. It was cooled by a water jacket around the barrel; steam generated in the water jacket could be conducted to a condensing device by means of a steam condensing tube, attachable to the end cap hose connection on the water jacket, the other end immersed in a water can.
Above: The Browning medium machine gun
The tripod mounting (Model 1918) was a triple-universal jointed tripod. It incorporated both an elevation and traversing mechanism. The following comment from the 11th Suffolk Home Guard history is amusing:
“The tripod mounting was in all probability responsible for more casualties to personnel in the shape of crushed, bent or bruised digits than any other weapon used. Any animal with three legs (if there is one) could surely never tie itself into knots as did this triple-universal jointed swine.”
Left: Browning mmg tripod
Right: The elevation and traversing
Some general data is as follows:
- Maximum effective range (M1 ammunition) – 2,500 yards
- Maximum usable range (M1 ammunition) – 4,000 yards
- Belt fed, woven fabric belt with 250 rounds
- Cyclic rate of fire, continuous – 400 to 525 rounds per minute (r.p.m)
- Slow rate of fire – 60 r.p.m
- Medium rate of fire (normal in battle) – 125 r.p.m
- Fast rate of fire – 250 r.p.m
- Weight of gun, water jacket filled - 36.76 pounds
- Weight of Tripod (Model 1918) – 45 pounds
Its use was principally for defence, the weight of the gun and tripod meaning it was not very mobile. It was to be sited to fire enfilade if possible. Most Home Guard units reconnoitered positions for their guns in the open, requiring simple weapon-pits or sandbag posts to be constructed. A firing position from a garden wall or a house however could be easily made by knocking a hole in the wall and if necessary building a platform of bricks or earth for the gun behind it.
Above: Left - a field emplacement that could be dug quickly. Middle - a field emplacement if more time is available. Right - a field emplacement that allows the gunner to stand behind the gun or sit in the bottom of the pit when not actually firing the gun.
Some units devised their own mobile mounts for the gun. Two examples are documented in Suffolk where Home Guard units devised mounts in an attempt to make the gun mobile and hence usable for offensive operations.
The Commander of the Ixworth Home Guard, Major Kilner M.C. , devised a simple mount consisting of two pneumatic tyres mounted on a square axle. A piece of hardwood was bolted to the axle with slots in it to take the front two legs of the tripod, which were bolted through the holes on the shoes to the wood. The rear leg was used to drag the gun by hand, or by bolting a draw bar bracket onto the hole through the shoe, could be towed by a car. Also attached to the hardwood was a try to carry two strapped ammunition boxes and a box for spare parts etc. It could be fired from the mount, with two chocks placed in front of the wheels and the spade end of the rear leg stamped well into the ground; it was actually found the gun was more stable on the mount than the tripod firing from firm ground, resulting in a closer grouping of shots. If the ground was uneven, the tripod could be adjusted on the mount by slackening the bolts through the shoes and adjusting the jamming handles or the gun could quickly be disconnected from the mount. Major Kilner submitted his design to the War Office for general production, mainly for the Home Guard but also the Field Forces. The design was not accepted, the reason given by the demand on factories by Field Forces.
“B” Company, 11 Suffolk Home Guard also came up with a wheeled platform, also for speedy mobility, but also with an addition of fixing an adaptation enabling the gun to be used at a sufficient trajectory to engage low flying aircraft.
Right: The mobile mount being demonstrated by "B" Company
11 Suffolk Home Guard
The Browning Heavy Machine Gun Mechanism Made Easy, Gale & Polden Ltd, 1942
Instructional Notes on the .300-inch Browning machine Gun (Provisional), WO, 1940
Home Guard, SFK 11, TNA
Photographic Record of G Company, 2nd Battalion Suffolk Home Guard, Major Kilner M.C., SRO