The Japanese Type 92 (M1932) 7.7mm Heavy Machine Gun (Kyuni Shiki Jukikanju)
The Type 92 was equipped with a small number of accessories that included:
- An anti-aircraft extension adaptor to be mounted on the tripod for anti-aircraft operations.
- A front anti-aircraft ring and rear blade sight. The AA ring sight is placed in the ring sight base located in front of the receiver and the rear AA post sight is slipped into the channel on the rear sight mechanism. The front and rear AA sights were kept in a fitted metal case when not in use.
- Three different telescopic sights were used, each with a fitted case.
- Tool and spare parts box. The takedown tools are particularly important and necessary for removal of the gas-jet plug and barrel.
- Handles for carrying the gun and tripod.
- A gun cover was also issued.
Three types of optical sights were used with the Type 92 heavy machine gun. The first was the Model 93 (1933). The 6-power Model 93 is a periscopic sight measuring 8.4 inches from top to bottom. The eyepiece is located well above the top of the receiver and was used for laying the gun. It was removed before firing. The Model 93 optical sight was affixed to a large base unit that attached to the top of the receiver. This base unit was separate from the telescopic sight and contained the various adjusting wheels.
The second type of optical sight was the Model 94 (1934). This 5-power sight was also a periscopic type measuring 12.8 inches from top to bottom. The eyepiece is level with the top of the receiver and was better supported on the sight base unit. This sight was affixed to the same large sight base unit with the adjusting wheels that was used with the Model 93 and was attached to the top of the receiver.
The third, and final, type of optical sight was the Model 96 (1936). This sight is a 4-power telescopic sight and mounts directly on top of the receiver and may be used while firing. The elevation wheel is located above and to the right of the eyepiece and is marked from 1 to 50 mils plus and minus. The deflection knob and scale are located on the left side of the sight. The single complete unit attaches directly to the top of the receiver.
The Type 92 tripod weighs 61 pounds. An elevating wheel is located to the front that raises and lowers the tripod head to the desired height. As the tripod head is lowered, the bottom of the vertical support column protrudes out the bottom of the tripod. A leather boot is attached to the bottom of the tripod to encompass and protect this vulnerable opening from dirt, mud and sand. The gun has two (left and right) trunnion studs located just forward of the receiver that lock into receptacles located on top of the tripod head. Fine adjustment controls for traverse and elevation are located on the tripod head beneath the weapon.
A unique feature of the Type 92 tripod is the means by which to easily carry the assembled gun and tripod (totaling 122 pounds) by three or four men in the manner of carrying a litter. The two front legs of the tripod each have a socket welded in place near the foot and were keyed to accept the carrying handles. The rear leg also had a keyed receptacle to accept a “U” shaped carrying handle. Wood or bamboo could also be used in field expedient situations.
The Type 92 (1932) heavy machine gun is a modified Hotchkiss-type weapon. Barrel life is unusually long as the gun rarely overheated due to the slow cyclic rate of fire, feed strips containing only 30 rounds and with its great number of cooling rings (25). The gun uses Model 92 (1932) 7.7mm semi-rimmed ammunition in ball, tracer and armor-piercing. An incendiary round can also be used. Another unique feature of the Type 92 is that besides having an ejection port cover that locks closed and is opened by retracting the cocking handle; it also had a feed strip entrance port cover that incorporated a feed strip roller bar that also opened when the cocking handle was retracted. The Earlier Taisho 3 version proved itself during the long wars against China in the 1930s and the later modified Type 92 was the standard machine gun during World War II. The Type 92 was nicknamed the “Woodpecker” by Allied soldiers during World War II due to its distinctive, slightly hesitant sound when firing. Since the weapon used a 30-round feed strip that hung somewhat heavily if not supported by the hand of the assistant gunner on the left side of the gun when first inserted into the feedblock, the first few rounds fired were relatively hesitant before picking up speed. This caused a sound uniquely characteristic to this weapon and easily identified in action.
- Safety. Turn the trigger thumb-piece clockwise for “safe.” When the feedstrip is removed, the bolt is locked in the rear position. When a strip is inserted and the bolt is unlocked, the can be fired by pressing on the trigger thumbpiece.
- To load and fire. Put the traversing handles into the lower, or firing position. Pull back the cocking handle and push it forward. The feed and ejection opening ports will automatically open when the cocking handle is moved. Insert a strip of ammunition from the left side of the feed mechanism with the rounds uppermost. The gun is now ready to be fired. The gun will continue to fire as long as the trigger thumb-piece is pressed forward or until the ammunition is expended, at which time the now empty feed strip is ejected from the right side of the weapon and the holding pawl rises up and holds the bolt open until the weapon is reloaded with a fresh ammunition strip. To adjust the gas cylinder, screw the gas cylinder plug in or out, enlarging or decreasing the length of the gas cylinder until the gun functions properly.
- To unload. Pull out the feed holding-pawl arm hook underneath the feedway on the left side of the receiver. Remove the feed strip. Check the chamber to be sure it is empty.
Always be sure weapon is unloaded and safe before disassembly.
- Backplate. Remove the backplate pin by turning it down to a vertical position and then pulling it out. Hold the backplate in place against the pressure of the operating spring and then carefully remove the backplate group, buffer assembly and operating spring.
- Bolt. Pull the cocking handle to the rear, and remove the gas piston, bolt lock and bolt. Align the lugs on the cocking handle with the openings on the side of the receiver and remove the cocking handle.
- Oiler. Push forward on the oil reservoir lock and raise up on the rear of the oil reservoir. Remove the oil reservoir retaining screw and lift the oil reservoir up and off of the feedblock.
- Barrel. Remove the gas-jet cover from the bottom of the gas cylinder. Unscrew the gas jet from the barrel using the specialized gas-jet removal tool found in the tool and spare parts box. Remove the barrel nut by unscrewing. Using the special barrel removal tool found in the tool and spare parts box, unscrew the barrel sleeve. Then turn the barrel one-half turn to the right and pull it out.
- Feed mechanism. Locate the holding pin located at the front and bottom of the feed box. Rotate this pin one-half turn in a downward direction and then pull it out. Remove the holding pawl and holding-pawl spring. Align the marks on the feed slide with the marks on the feed box, and drift the feed-slide pin out to the front of the feed box. Slide the feed slide to the left, removing the feed pawl and feed-pawl spring at the same time.
- Assembly. To assemble the weapon, proceed in the reverse order to that followed in stripping.
(I would like to thank renowned Japanese military weapons historian, Mr. Edwin Libby, for his considerable assistance in providing key information for this article. Without his valuable help, this article could not have been completed.)