Spigot mortar

One outstanding characteristic of Japanese armament was the large variety of type and sizes of Mortars (Kyuho) in use. They were used not only as Infantry (Hohei) support weapons but also as Artillery Pieces (Ho). They ranged in size from the 50-mm Grenade Discharger (Tekidanto) to the 320-mm Spigot Mortar ( Spigot Kyuho)... 

Accdg to Ref 3, pp 389—90, the Shell fired by Spigot Mortar was cylindrical in shape (resembling a bomb) with ogival nose and finned tail section hollowed out to inside diam of 10.12 inches and length 14.5 inches so that it could fit over the spigot. The shell contd... 

German Spigot Mortar Projectile. See PATR 2510(1958), pp Ger 187-R to.Ger 188-L (Illustrated)... 

Spigot Mortar. A mortar which propels a warhead larger than the bore of the mortar by means of a closed tube (spigot) attached to the warhead and extending into the mortar. The force of the proplnt within the mortar acts upon the tube, thus propelling the warhead toward the target Ref J. Quick, Dictionary of Weapons and Military Terms , McGraw-Hill, NY (1973), 415... 

NOTE BEFORE ASSEMBLING PIPE. CLEAN AND SAND LIGHTLY THE SHOULDER OF BELL AND END OF SPIGOT. APPLY MORTAR TO SPIGOT END AND TO SHOULDER OF BELL. THEN SEAT AND CENTER SPIGOT INTO BELL. TIE DOWN PIPE TIGHTLY BEFORE CAULKING JOINT. 

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