on the bottom of the receiver. The receiver has no recoil shoulder. The recoil is transferred to the stock by a recoil block which fits over the studs and between the receiver and the floorplate. This recoil block has one flat side (inletted into the stock so the flat side is to the rear) which has enough area to absorb the recoil and prevent set-back of the action in the stock.
The Type 38 Japanese action was designed to eliminate one of the major weak points found in most modern military bolt-action rifles—the wrist or grip of the stock. In the Type 38 action strengthening the grip area was done with tangs connected to the receiver and trigger guard. The upper tang, made as a separate part, was milled and joined to the receiver to act as a solid extension to the receiver when the action is in the stock. The separate lower tang was also mated to the rear of the trigger guard. The rear guard screw passes first through lower tang, then through the trigger guard and threads into a square stud in the receiver. The ends of the tangs are connected by a long screw through the top tang and stock which threads into the lower tang. The tangs extend well past the smallest part of the grip, greatly strengthening the weakest area of the stock.
Arisaka Type 38 (1905) 6.5mm action, minus breech cover.
All bolt-action rifles are more or less open to the elements. Dust, mud, sand, water and sleet can get into the action through the top receiver openings and can cause problems.
Japanese designers, evidently familiar with this shortcoming, decided that the action should be covered as much as practicable. The result was a very simple arrangement. Two longitudinal narrow grooves were cut into the receiver, one high on the left receiver wall, the other on the low right receiver wall. A curved strip of spring-tempered sheet metal, its edges folded in, was made to fit over the receiver and slide in the grooves. The bolt handle projected through a hole in the rear of this cover allowing the bolt handle to be raised and lowered. The bolt pulls the cover backward and forward with it as the action is opened and closed. This cover did effectively close the main receiver opening, but it still left a big opening around the base of the bolt handle where dirt could get in. The action was more difficult to operate with the cover in place than with the cover removed. Since many captured rifles were minus their breech covers, it seems that some Japanese soldiers discarded them.
Ample provision was made in the Type 38 Arisaka action to allow powder gases to escape harmlessly in the event of a ruptured case head or pierced primer. Two small holes in the top of the receiver ring provide vents for any gas escaping into the locking-lug recesses. A single large oblong hole in the bottom of the bolt, just behind the locking lugs, allows gas to escape into the left locking lug raceway and thence to the auxiliary lug opening in the top of this raceway, just to the rear of the receiver ring. Should any gas be directed rearward in this raceway, it would be deflected by the bolt stop lug, and if any got beyond this point the safety would deflect it from the shooter’s face. Should a large volume of gas get inside the bolt through the firing pin hole, all of it could not escape through the large vent in the bolt. It would expand into the inside of the hollow striker, but it would not reach the shooter because of the solid safety cap.
Type 38 Japanese 6.5mm action, open.
Left side of the Type 38 Arisaka action.
Type 99 Arisakas
In the late 1930s Japan was preparing for war. Type 38 Arisaka rifles were good, and so was the 6.5mm cartridge, but measures had to be taken to speed up production of the rifles and for several reasons a larger caliber was also desirable. Thus, in about 1938, steps were taken to modify the Type 38 (1905) action for easier, faster, less costly manufacture. The Type 99 (1939) Arisaka action was the result. At the same time they adopted a new cartridge, commonly known as the 7.7 Japanese or 31-caliber Japanese.
Here is a brief description of the 7.7mm-caliber rifles and carbines based on the 99 action, or on further modifications of it.
1. Type 99 (1939) Long Rifle. About 9 pounds, 31.4” barrel, 50” overall.
2. Type 99 (1939) Short Rifle. About 8.5 pounds, 25.75” barrel, 44.25” overall. The standard Japanese infantry rifle used during WWII.
3. Type 99 (1939) Sniper Rifle, same as number 2 above except fitted with a 2.5x scope with a detachable off-set mount. Bent down bolt handle.
4. Type 99 (late version ) Short Rifle, same as number 2 above but more cheaply made. Identifying features are: wooden buttplate, fixed aperature rear sight, no model markings. See text for specific details of this and the paratroop rifles.
5. Type O Paratroop Rifle. About 8.75 pounds, 25.75” barrel, 44.25” overall. Very rare model.
6. Type 2 (1942) Paratroop Rifle. About 9 pounds, 25.9” barrel, 44.25” overall.
The main identifying features of all rifles based on the Type 99 action are the stamped trigger guard, hinged magazine floorplate, and lower tang extending below the pistol grip. Type 99 Long, Short and Type 2 Sniper rifles usually had chrome-plated bores and bolt faces, and all except the sniper model had straight bolt handles. Sliding breech covers were also standard.
The Type 99 Action
Just as the 1903A3 Springfield action was a modified version of the 1903 Springfield action to make it easier to manufacture, the Japanese 99 action bore the same relationship to the earlier Type 38 action. In neither case did this result in the action becoming less reliable nor weaker. Although the quality of the finish suffered, the modified Springfield and Arisaka actions were unaffected as far as military use was concerned.
The following are the most notable outward changes and modifications made in effecting the change over from the Type 38 (1905) 6.5mm action to the Type 99 (1939) 7.7mm action:
1. The separate recoil block was eliminated; the 99 receiver was made with an integral recoil lug of ample size, which was an improvement.
2. Instead of milling an L-slot in the receiver bridge for the bolt handle, most of the metal below this slot was cut away on the 99 receiver. This still left enough metal for a safety lug for the bolt handle in the event the front locking lugs should fail.
3. The integral bolt-stop housing on the receiver was replaced by a copy of the Mauser bolt-stop and ejector. The bolt-stop, attached to a lug on the receiver, is held in place by a pointed screw turned in from the top, with the ejector pivoting on this same screw. The ejector is tensioned by a separate small spring wedged under the heavier bolt-stop spring mortised in the bolt-stop.
Top view of the Type 38 Arisaka action. Note twin gas-escape holes in the receiver ring, the Japanese Imperial seal and other Japanese markings on the receiver ring, the clip-charger slot in the receiver bridge, the L-shaped slot for the bolt handle, and the oval grasping ball on the straight bolt handle.
4. The auxiliary lug and the left (top) locking lug are milled entirely through for the ejector.
5. Sheet metal stampings were used for several parts on the 99 action. These include the upper tang, lower tang and trigger guard bow, magazine floorplate and floorplate latch.
6. The magazine floorplate is hinged to the front of the magazine plate.
7.
