Gun type fuze: H.E. projectiles for the 47-mm antitank gun, 57-mm tank gun, 75-mm guns, and 105-mm guns. This fuze is also used in incendiary and smoke projectiles for 75-mm guns.

Howitzer-mortar type fuze: Used in H.E. projectiles for 70-mm howitzer, 105-mm guns and howitzers, 120-mm howitzer, and 150-mm howitzer. It is also used in a smoke projectile for the 150-mm howitzer.

Over-all length (with gaine): 3 9/16 inches.

Over-all length (without gaine): 2 7/8 inches.

Maximum diameter: 1 inch.

Threaded length: 0.5 inch.

Number of threads: 5, right-hand.

Construction: The fuze body, of either black steel or brass, is made into two parts fit-ted together with threads (L.H.). The head of the aluminum striker protrudes from the fuze and is held in the unarmed position by four wedges which rest on a raised collar of the lower fuze body and are held in place by an arming collar. The arming collar is sup-ported by latch springs. The striker in the armed position is held from the primer by a coi-led spring.

Operation: Set-back causes the set-back or arming collar to move down until the notch on the inner side of the collar is engaged and held down by the latch springs. Centrifugal force moves the wedges out, arming the fuze. On impact the striker is forced down, over-coming the spring tension, to strike the primer.

Remarks: The howitzer-mortar and the gun type fuze are identical in constrcution ex-cept that the howitzer-mortar fuze has a weaker latch spring, which allows for arming with a smaller amount of set-back force.

Figure 323 – Type 88 Instantaneous (Gun and Howitzer-Mortar) Fuze.