The heart of Maxim's self-loading system was the lock, a complex but very efficient loading and firing mechanism. The Maxim was adopted by armies around the world, and remained in wide service even into the 1970s.

At left is a close-up view of the lock's extractor.

1. When the lock moves into battery the extractor slides upward and grabs a belted round, locking it below the "a" catch.

2. When a round fires the lock moves rearward and the extractor strips the round out of the belt and then slides down (#2), aligning the round with the chamber of the barrel.

3. As the round enters the chamber the extractor slides upward until the chambered round is caught between "b." and "c." in the #2 position. As this happens the extractor is grabbing another belted round at the #1 position, and a spent case is deposited in the discharge tube. As subsequent cases are pushed into the tube, they are eventually dumped on the ground in front of the receiver.

Left: I made this animated GIF that I hope will help in understanding the cycle. At the end of the cycle the empty cartridges are expelled through the front of the gun via a tube.
Maxim variants were many, and were adopted around the world. I am only presenting a few here - enough to give a general idea of the weapon. I highly recommend anyone with an interest in the Maxim acquire a copy of The Devils Paintbrush, by Dolf Goldsmith.  It is an excellent book with 568 pages of photos and narrative that give an in-depth look at the incredible diversity of Maxim models. You can buy a copy from the author by visiting his Web site:  http://www.dolfgoldsmithgunbooks.com/ NOTE: Much of the information on this site was found in The Devil's Paintbrush.
THE EARLY MODELS
A Maxim Nordenfelt model 1895, ordered by Argentina, one of the early purchasers of the Maxim. Albert Vickers, the main financier of The Maxim Gun Company, bought The Swedish competitor, Nordenfelt in 1888.

A Maxim Automatic Machine Gun, Caliber 30, Model of 1904, purchased by the United States. The large muzzle booster was needed to cycle a heavy barrel 1" in diameter.

Clyde Hooker with his 1904 Maxim in Hawaii during WW1.
Thanks to his grandson Steve for sharing this photo.

A captured German Maxim MG08 on a sledge mount. Note the bullet holes in its water jacket.
An MG08 on a sledge mount. Thank you to John for providing these images.
In Belgium, Maxims on carts were often pulled by dogs.

In 1906 the "New Pattern" or "New Light" Maxim was introduced. It had a provision for head spacing, a lock which was easier to strip, as well as a smaller feed block made from steel instead of brass. The water jacket was made of steel and corrugated to allow for thinner, lighter material, and a muzzle booster was introduced. Though it was the last and best of the British Maxims, it did poorly and few were sold. The design itself did very well and went on to enjoy the largest production of any Maxim. Russian adopted the design as their Maxim 1910. Produced in great numbers, it was Russia's dominant heavy machine gun during WW2. It saw heavy use with the North Koreans during the Korean War.                                    From The Devil's Paintbrush

SPECIFICATIONS
Sokolov Pulemyot Maxima (Maxim M1910)

Nation...................................
Date of design......................
Production period.................
Service duration...................
Operators.............................
War service..........................
Variants................................
Type......................................
Operation.............................
Caliber .................................
Ammunition .........................
Muzzle velocity ...................
Capacity...............................
Weight - Gun .......................
Weight - Sokolov Mount ....
Overall length .....................
Barrel length .......................
Rate of fire ..........................
Effective range ....................

USSR
1910
1910 to 1939, 1941 to 1945
1910 to 1970's
USSR, China, Korea
WWI - WWII - Korea

M1910/30
Machine Gun
Automatic only, recoil operated, water-cooled
7.62mm
Heavy Ball M1930; 185 gr bullet, 50 gr charge
2830 fps
250-round fabric belt
52.8 lbs, unloaded
79 pounds
43.6 in
28.4 in, 4 grooves, right hand twist
520-580 rpm
1000m (1100 yds)


A Russian Maxim 1910 with belted ammo. To
the right of the 1910 is a Mosine-Nagant rifle.
On a wheeled Sokolov mount the 1910 was well suited for infantry operations. The wheels spared soldier's having to carry both mount and gun.
The Russian Maxim 1910 was imported into the United States in some numbers, intended for the collector community. It was a great opportunity to get a vintage Maxim. The "piano" box attached to the left rear bar held a spare lock. The large filler cap on the top of the water jacket was big enough to accept handfuls of snow or ice in the absence of water. The 1910 is chambered for the Russian 7.62x54R cartridge.

The crate has Cyrillic markings, and is numbered to the mount, in this case #238.
In order to comply with US restrictions on importing live machine guns, the gun was imported as a parts set. It was missing only the right side plate, the ATF controlled part. The smaller pieces of side plates just to the right of center in the above photo are for necessary dovetails, trunnion spacers and internal cam plates which will be needed for the approved semi-auto side plate. The Sokolov mount, pictured at right, came in a storage crate along with the heavy steel shield.

Inside the crate was a pink slip documenting the arsenal refurbishing of the mount. It is dated 1969, and is numbered 238. Cold War Russia was keeping it's inventory ready.

Above: Maxim spare barrel cases in both wood and leather.
Right: The open end of the leather barrel case showing a barrel in place.

View showing fusee cover. The fusee and spring create torsion
on the lock, causing it to move back into battery after recoil.


Maxim Steam Chest. Steam generated by the hot barrel in the water jacket passes through a hose and into this can, where it both hides the gun's position by containing the steam, and collects the condensed water for reuse.


A poster depicting a Russian Maxim.

A rear view.

Grease brush.
The spade grips. The handles have grease in them and the tops, which unscrew, have brushes with which to apply the grease to the 1910's internals.

Referred to as "3 in 1 cans", oil solvent and antifreeze can are designed to fit into an ammo box.
At left: A case of Russian 7.62x54R ammunition.
Above, center: A 7.62x54R cartridge.
Above, right: 3 in 1 cans outside their ammo box

The Izhevsk factory markings on the top cover.
The Izhevsk factory marking at left is thought by some (until recently, me included) to be a Tula factory logo. Many thanks to Dmitry for providing the following information:
"There were several plants producing firearms in Izhevsk during the WW2. In July, 1942 Plant #74 (Izhevsk Engineering Plant, Izhmash) was divided into Plant # 74 and Plant # 622 (Izhevsk Mechanical Plant, IMZ). These plants never produced Maxim MGs. Izhmash marking is an arrow inside a triangle. IMZ has an arrow inside a circle inside a triangle.
IMZ logo
Izhevsk Motorcycle Plant (Plant # 524) stopped producing motorcycles shortly after beginning of the war. It had been producing Maxim MGs (and only Maxim MGs) since 1942 till the end of war. It's marking was an arrow inside hexagon. After the war Izhevsk Motorcycle Plant produced hunting rifles.
IzhevskPlant524
The first AK-47 was produced there. It stopped producing firearms in 1949 and started producing electronic devices. Tula Arsenal was evacuated to Izhevsk in 1942. So there can be weapons with Tula markings, but produced in Izhevsk. After coming back to Tula the Arsenal changed its markings from an arrow inside a star to a hammer inside a star. And in 1945 to T inside a star. Here you can find evolution of Tula Arsenal marking ( it's in Russian) http://www.tirspb.ru/content.php?nodeid=144 "

Russian gunner's kit with tools for cleaning the gun and a few spare parts for performing minor repairs.

A Finnish gunner's kit for the 1910. Many Russian 1910 Maxims were captured and used by the Finnish Army.
This print, entitled "Into the Clouds", appeared in the December 15, 1904 issue of Vanity Fair magazine.

An aluminum feed block. Feed blocks were usually steel, but less frequently made of brass or aluminum.

The tin box in the Finnish gunner's kit contains shim washers for head spacing the gun and other spare parts such as a firing pin and springs.

A spring scale is used to adjust the tension on the fusee spring.