Making passages in minefields is difficult and dangerous work, consuming large amounts of time and causing many losses. Frequently, it is not possible to make passages in advance, and they have to be made during the offensive, which inevitably delays the operation and results in missed deadlines.
Of many methods of minefield clearing, the method of using explosive charges found widespread use. According to experience (Military Engineering magazine issue #3 for 1942, page 45, Military Engineer 1st Grade Morin's article), passages up to 8 meters wide can be cleared using properly selected charges.
The proposed device mechanizes the above procedures and allows the tank to clear passages in minefields without losing speed during an offensive.
The same device allows for the creation of a shrapnel cloud in front of the tank, striking all targets in an area 50-100 meters wide. This mode of operation is useful when pursuing the enemy.
The device consists of a magazine (1) made from 10-20 mm thick steel (for protection from bullets and shrapnel), loaded with F-1 hand grenades equipped with a special detonator or custom made charges up to 3 kilograms in weight.
The firing mechanism consists of a round or rectangular barrel (2) with a plunger (3). The spring (4) pushes against the end of the tube (5), which is adjustable to control the power of the spring. The spring is retracted automatically using a roller chain (6). The chain has an edge (7), and is moved using the transmission gears (8, 9), and the crankshaft (10) from the tank's engine or drive wheel.
When the chain moves, the edge (7) grabs on the rim (11) of the plunger (3) and pulls it back, compressing the spring (4), until the plunger clears the magazine, which will cause a grenade to fall into the barrel (1).
Upon further motion, the edge (7) slips off the rim (11) and the plunger (3) moves forward to throw the grenade out of the barrel to a distance of 5-20 meters, set by adjusting the end of the barrel (5).
The grenades or charges must detonate 0.5 meters before hitting the ground (the optimal height to clear mines) or when they hit the ground. Many detonators can be proposed. For instance, the F-1 grenade can be equipped with a #8 capsule detonator, put on a screwed-in cap with an opening that is filled with a powder charge. The time of burning can be set so the grenade explodes 0.5 meters above the ground. A grenade modified this way can be found on sketch #2.
The ignition of the powder can be achieved by sprinkling the grenade in KS fluid from a reservoir (12) when it leaves the barrel (2), where it is pressurized by inert gases (engine exhaust), fed in by two pipes (13) and equipped with an automatic valve (14), opened by the grenade when it flies out. This device is shown on sketch #1.
An explosive charge (several TNT charges tied together) can also be equipped with a similar detonator.
Other methods can be used to ignite the powder: friction igniters, burners, electrically heated coils, etc.
Mechanical methods of detonating the grenade, such as an inertial detonator (as with the RPG grenade), a lever detonator, drawn back when the grenade launches, or a contact detonator from mortar rounds.
The mechanism can also be modified to fire rounds from company or battalion mortars, which will not require any modifications and be effective both in destroying objects surrounding the tank and clearing minefields.
In cases of necessity, 2-3 mechanisms can be installed on one tank, clearing a wide area. The magazine is carried in front of the tank for safety, in case the explosives detonate after being hit by a shell, but it can be placed inside the tank to improve maneuverability.
The magazine should be equipped with a spinning loading gear, like on counting or wrapping devices, to make the loading process more reliable.
Senior Lieutenant Bogoslovskiy"