The RKG-3 was designed to replace the RPG-6 and RPG-43 anti-tank grenades. The original RKG-3, which was adopted for development in 1950, used a basic shaped charge with a steel sleeve capable of penetrating 125 mm of rolled homogeneous armor at an angle of up to 30° to the normal. In 1957, the improved RKG-3M went into production, which has a cumulative funnel with a copper lining and armor penetration of 150 mm. In the late 1950s, two more modifications of the grenade were created - RKG-3E and RKG-3EM (GRAU index - 7G1). The grenades received an improved funnel shape. The armor penetration of the RKG-3E (with a steel funnel) is 170 mm, the RKG-3EM (with a copper funnel) is 220 mm. In the 1970s, the RKG-3 grenade was replaced in the Soviet Army by the RPG-18 rocket-propelled grenade.
Designed to combat enemy tanks, self-propelled artillery, armored personnel carriers and infantry fighting vehicles, as well as to destroy long-term and field defenses.
1. The body of the grenade is cylindrical, designed to accommodate a bursting charge and a fuse. 2. The handle serves for the convenience of throwing the grenade and activating the percussion mechanism. It consists of a body, a movable clutch with a spring, a folding bar, a folding cap with a bar and a safety check with a ring. The handle houses the percussion mechanism, a stabilizer and a safety device. The body of the handle is sealed; in front it is closed with a parchment circle, and at the back between the movable clutch and the cap there are felt pads. The movable clutch has a notch for screwing onto the cover of the grenade body. On its side surface there is an eye with a hole for the safety check and two grooves. Using the eye and check, the movable clutch is connected to the folding bar. In one groove of the movable coupling, the spring end of the folding bar is placed, and in the other, the end of the folding cap bar with a ball. 3. The percussion mechanism is designed to ignite the fuse detonator capsule. It consists of a housing, a tube with a flange, a striker housing, a striker, a main and counter-safety springs, safety balls and an inertial weight. The striker housing is placed in a tube with a flange and has four holes for safety balls. The striker and main spring are located inside the housing. Two large safety balls hold the striker housing in the tube, and two small ones hold the striker in the striker housing. The counter-safety spring does not allow the inertial weight to move during the grenade's flight. 4. The stabilizer is designed to give the grenade a directed flight with the bottom of the housing forward. It consists of a fabric cone, four wire feathers, a sleeve, a ring and a spring. 5. The safety device includes four fuses that ensure safety when handling the grenade and its flight. The first fuse - a safety check - connects the movable coupling with the folding bar and ensures safety when handling the grenade. It is turned off before throwing the grenade. The second fuse ensures the safety of the grenade in case of an accidental fall if the safety check is pulled out. It consists of a folding cap bar with a ball, a movable coupling and its spring. The fuse turns off at the moment of throwing the grenade. The third fuse ensures the safety of the grenade after throwing (when the second fuse has worked) in case of an accidental impact on an obstacle located closer than 1 m from the person throwing the grenade. It consists of a rod with a cap and a spring, a movable and central tube, a nipple and two balls. The fuse is turned off by the stabilizer after it is opened during the grenade's flight. The fourth fuse - a counter-safety spring - ensures the safety of the grenade during flight, holding the inertial weight from moving forward. 6. The bursting charge is designed to penetrate armor (concrete) and destroy strong obstacles. To form a narrow jet of high-density gases (tens of hundreds - several thousand atmospheres) during an explosion and direct its action on the armor (obstacle), the charge in the front part has a conical cumulative funnel. In addition, there is free space (without explosive) between the bottom of the case and the cumulative funnel, which provides optimal conditions for the formation of a cumulative jet. The bursting charge consists of the main and auxiliary charges, between which a cardboard gasket is laid. 7. The instant-action fuse is designed to detonate the explosive charge of a grenade. It consists of a sleeve and a bushing. The bushing contains a detonator capsule, and the bushing contains an auxiliary detonator.
When hitting a target, the grenade explodes instantly, a jet of high-density and high-temperature gases pierces the armor of modern technology and other strong obstacles. 1. Before throwing a grenade. Take the grenade out of the bag, unscrew the handle, insert the fuse into the body tube and screw the handle all the way in. The striker is held by small balls in the striker body, pressing the mainspring. The striker body is held from moving forward by large balls in the tube with a flange. The folding bar is connected by a safety catch to the movable clutch of the handle and the bent end with a folding cap. The spring end of the folding bar is located in the groove of the movable clutch. The ends of the safety catch are spread apart and hold it firmly on the handle. 2. When throwing a grenade. The grenade is taken by the handle in the hand, the ends of the safety catch are brought together, after which it is pulled out. When the catch is pulled out, the movable coupling and the folding bar are disconnected. When swinging to throw the grenade, the grenade body together with the movable coupling moves away from the handle, compressing the spring of the movable coupling, releasing the ball and the spring end of the folding bar. 3. After the grenade is separated from the hand, the handle body moves to the grenade body under the action of the spring of the movable coupling and takes the previous (before throwing) position. The folding cap moves back from the handle under the action of its spring, rotates the folding bar and, freeing itself from engagement with it, separates from the handle. The stabilizer spring pushes the stabilizer out of the handle, which, under the action of wire springs and air resistance, opens and pulls out the movable tube; at the same time, the balls of the third fuse that hold the rod are released. The rod, under the action of its spring, leaves the striker (the third fuse has been triggered) and releases the large balls, which in turn release the striker body. The forward movement of the inertial weight and the striker body is prevented by the counter-safety spring and friction. Small balls located in the walls of the striker body do not allow the striker to move forward. 4. When meeting a target (obstacle). At the moment the grenade hits the target (obstacle) with the bottom of the body or the side part, the counter-safety spring is compressed under the action of the inertial weight, and the striker body moves forward until the small balls enter the groove of the tube with the flange and release the striker. The firing pin, under the action of the mainspring, moves forward sharply, pricks the detonator of the fuse, it ignites and causes an instant explosion of the grenade.
GRAU index – 57-G-732 Hand-held cumulative grenades RKG-3 are packed in wooden boxes of 12 pieces. In a box with RKG-3: 12 cases wrapped in bitumen paper, two boxes with handles (6 pieces each), two cans with fuses (6 pieces each), a knife (key) for opening boxes and cans. The weight of the box is 23 kg. In a box with RKG-3E: 6 packages with cases (two cases each), one box with handles, one can with fuses, two knives for opening boxes and cans, two instructions for the knives. The weight of the box RKG-3E (RKG-3EM) is 24 kg.