German Explosives
Anti-Tank Rifle Grenade (Gewehr Panzergranate)
Overall Length: 6.4 inches
Maximum Diameter: 1 and 3/16 inches
Filler: TNT
Weight of Filler: 1.75 ounces
Range: 50 yards
Total Weight: 8.8 ounces
Color: Front half is black and back half is aluminum
Description: This grenade is fired from the rifle 3cm discharger cup (Schiessbecher) which can be fitted to most types of German rifles. It is constructed in two parts, the head and the stem. The head is a seamless steel tube with the forward portion containing a hollow charge cone and the explosive filling, being closed at the forward end by a light ballistic cap. The main filling of TNT is poured around the cone and there is a cavity formed in the after part of the main filling in which the exploder of penthrite wax is inserted.
The stem is made of light alloy or aluminum and is screwed onto the head of the grenade. The stem is divided into two compartments, the lower containing the fuze, the upper the gaine. In the septum is a small flash pellet held in place by a perforated screw plug. The gaine consists of a light alloy case into which is inserted a light alloy top hat containing the detonator, the space between being filled with penthrite wax. A preen-graved driving band is formed around the stem 6mm from the rear.
The fuze is in the after portion of the stem and consists of a striker over the top of which fits a retaining spring with four prongs bent downward into grooves in the striker body. Around the striker body is an arming collar which has two grooves cut on the inside. An arming spring is compressed between a lip on the arming collar and a second collar at the bottom of the striker body. Around the inside of the arming collar and resting on the striker body is a steel tape which acts as an additional safety device and prevents any possibility of the fuze being accidentally armed when screwing on the base plug.
The entire assembly is closed by a base plug which positions the fuze by a stem which fits into a recess in the rear of the striker body.
Operation: On firing, the shock of discharge causes the arming sleeve to set back against its spring. The four prongs of the retaining spring are forced out of the lower groove in the arming sleeve and engage in the upper groove, retaining the arming sleeve in its lower position. This allows the steel tape to unwind and the striker is then free to move forward on impact firing the gaine.
37mm H.E. Anti-Tank Stick Grenade
Overall Length: 29 and 1/8 inches
Length of Stick: 16 and 7/16 inches
Length of Body: 12 and 1/4 inches
Total Weight: 18 pounds 12 ounces
Weight of Filler: 5 pounds 5 ounces
Explosive Filler: Dinitroanoline with TNT
Description: The complete round, which is made up of the hollow charge stick grenade and the propellant, is fired from the 3.7 PAK gun.
The stick grenade has a steel rod which fits into the bore, and a concentric perforated sleeve which fits around the barrel of the gun. A pressed steel cap forms the nose of the grenade giving it the required stand-off distance. The hollow charge is at the rear of the steel cone and consists of two blocks of dinitroanoline with TNT. Two detonators are set in the base of the grenade, one facing in each direction. A nose fuze of the instantaneous percussion type and a tail fuze, also instantaneous are present.
The steel rod which fits into the bore of the gun is a hollow tube closed at the base end. The base fuze is a percussion type fuze very sensitive to shock. It is armed by setback which releases a spring loaded detent allowing a steel ball to move away from the striker. Upon impact the striker moves forward against the action of a very weak creep spring.
The nose fuze consists of a striker held away from the primer by a creep spring and a coiled spring. Around the coiled spring is an inertia pellet resting on four fingers of a stirrup spring fixed in the base of a stirrup spring retainer. The inertia pellet has a groove cut around its internal circumference.
Two detonators are located at the base of the main charge. One detonator faces toward the nose fuze to receive the flash from there, and the other detonator faces the tail fuze to receive its flash.
The propelling charge is contained in a steel cartridge case. The charge consists of diethylene glycol dinitrate tubular stick powder with an igniting charge of nitrocellulose granular powder, and a percussion type primer consisting of mercury fulminate and black powder.
Operation: On discharge, the inertia pellet of the nose fuze is driven downwards and the ends of the stirrup spring are forced into the groove of the inertia pellet thus holding it down. The clock spring is now held in position by the collar of the striker pin and the stirrup spring retainer. On deceleration, the clock spring flies outward, assisted by centrifugal force, into the recess in the fuze body in the fuze body. At the same time the base fuze is being armed. In the event of direct impact, the nose fuze will function the grenade, but in the event of graze action, the base fuze will function the grenade.
Large Anti-Tank Rifle Grenade (Gross Gewehr Panzergranate)
Overall Length: 7 inches
Maximum Diameter: 1 and 3/4 inches
Weight of Filler: 4 and 1/2 ounces
Filler: TNT
Range: 100 yards
Total Weight: 13 and 1/2 ounces
Color: Black overall
Description: This grenade is fired from the rifled 3cm discharger cup (Schiessbecher) which can be fitted to most types of German rifles. It is of the hollow charge type and consists of a steel head containing the explosive and light alloy or steel and plastic stem containing the fuze and gaine. The propelling cartridge contains a wooden bullet.
The body which is of pressed steel contains a steel cone around which the main filler of TNT is cast. A steel washer with a small central hole rests on the open end of the cone and above the latter is a steel ballistic cap. At the bottom of the TNT is an exploder pellet of penthrite wax.
Two varieties of the stem have been found, one entirely of light alloy, the other of plastic with a steel shank by which it is screwed on to the head of the grenade. At the base of the stem is a rifled band which corresponds with the rifling in the discharger cup. The stem is divided into compartments by a perforated septum, the lower containing the fuze, the upper the gaine. In the septum is a small flash pellet held in place by a perforated screw plug. The gaine consists of a light alloy container into which is inserted a light alloy top hat containing the detonator, the space below being filled with penthrite wax.
The fuze is in the after portion of the stem and consists of a striker over the top of which fits a retaining spring with four prongs bent downward into grooves in the striker body. Around the striker body is an arming collar which has two grooves cut on the inside. An arming spring is compressed between a lip on the arming collar and a second collar at the bottom of the striker body. Around the inside of the arming collar and resting on the striker body is a steel tape which acts as an additional safety device and prevents any possibility of the fuze being accidentally armed when screwing on the base plug.
The entire assembly is closed by a base plug which positions the fuze by a stem which fits into a recess in the rear of the striker body.
Operation: On firing, the shock of discharge causes the arming sleeve to set back against its spring. The four prongs of the retaining spring are forced out of the lower groove in the arming sleeve and engage in the upper groove, retaining the arming sleeve in its lower position. This allows the steel tape to unwind and the striker is then free to move forward on impact, firing the gaine.
Next Time: German Mines and Grenades (Part 16)
Source: German Explosive Ordnance Vol. 1: Bombs, Rockets, Grenades, Mines, Fuzes & Igniters
