240 mm turbojet blast projectile M-24F (M-24FUD)

  • 1 - fuse;
  • 2 - screw;
  • 3 - transient bushing;
  • 4 - locking screw;
  • 5 - gasket;
  • 6 - tetril saber;
  • 7 - tetril draughts;
  • 8 - body;
  • 9 - bursting charge;
  • 10 - the bottom;
  • 11 - igniter;
  • 12 - gunpowder charge;
  • 13 - camera;
  • 14 - aperture;
  • 15 - locking screw;
  • 17 - nozzle bottom
  • 20 - candle
  • a - centrifugal thickening

The M-24F turbojet blast projectile (index 53-F-961, ballistic index TC-59) consists of head and missile parts.

The head part of the projectile consists of the hull 8, bottom 10, transition sleeve 3 and explosive charge 9 with an additional detonator, consisting of a tetrile 6 and two TNT 7 checkers. The explosive charge (TNT) is covered by a plastic bushing. When the projectile is finally equipped, the fuse (B-25) is screwed in place of the bushing and locked with a screw 2 1.

The rocket part of the projectile consists of chamber 13, powder charge 12, ignition 11, aperture 14, nozzle bottom 17 and candle 20. The powder charge consists of nineteen cylindrical single-channel draughts of FSG-2 nitroglycerine powder or KDSI nitroxylitane powder. Igniter 11 is designed to ignite the gunpowder charge. It consists of 90g of smoke powder placed in an aluminum shell. The igniter is enclosed in the safety disc 19 and is fixed in it by the feet. The flame retarder with a safety disk is inserted into the annular duct of the bottom and fixed with spring feet in it. Diaphragm 14 prevents unburned parts of the powder charge from escaping through the nozzle openings and together with the safety disc holds the powder charge checkers from moving in the chamber. The diaphragm is inserted into the nozzle bottom and secured with screws 15.

In the nozzle bottom 17 there are sixteen nozzles with their axes inclined at 15° to the projectile axis. This arrangement of the nozzles ensures the rotation of the projectile around its axis, which is necessary for the stable flight of the projectile. On the outer surface, the nozzle bottom has a dart, which includes a front stop of the war machine guide to keep the projectile from moving forward.

To protect the gunpowder charge from moisture, the nozzles are closed by cardboard and metal rings, which are pressed into the nozzle bottom and destroyed when the gases flow through the nozzles. A candle 20 with PP-9 pyrophatron is screwed into the central tapped hole of the nozzle bottom, which ignites the rocket fuel when an electric impulse is applied.

The candle consists of the body 5 with contact 7, insulated from the body by insulators 6, tip 2 with tube 1, PP-9 pyroelectron and spring 3. The pyrotechnic consists of a sleeve 8, a contact core 10, a contact cup 9 and two electric fuses 11.

The electric igniter represents resistance from a platinum-iridium wire attached by one end to a contact core and by the other to a contact cup on "weight". The platinum-iridium wire is coated with an initiating agent. The initiating agent ignites the smoke powder pressed into the sleeve. The igniter has a resistance of 0.15-0.8 ohm. The projectile is fired in the following way. Electric current from the contact of the folding arm of the guide through the contact of the candle and the contact core enters the wire of the igniter pyropropatron and inflames it, resulting in the igniter, which ignites the smoke powder of the pyropropatron. A ray of fire from the pyropropatron, passing through the tip of the candle and the channel of the central checker, burns aluminum foil of the ignitor and ignites the ignitor. The ignition ignites the powder charge of the projectile. As the powder gases flow through the nozzles, a reactive force is generated, which informs the projectile of its progressive and rotational motion.

The M-24FUD extended range projectile (index 53-F-961U, ballistic index TS-64) differs from the M-24F as follows: the head part has less weight of explosive charge; the detonator of explosive charge consists of one TNT and one Tetril draughts; the powder charge consists of seven thick-water single-channel powder draughts RSI-12K.

The M-24F and M-24FUD rounds are equipped with B-25 and B-24 fuses. Fuse B-25 head, shock action, with installation for instant action and two installations for slow motion. The fuse provides shattering or blast action of the projectile at the target and is safe on the entire trajectory of the projectile. The B-25 fuse consists of a housing with a mounting device, a head with a double-acting impact mechanism assembled in it, a safety and long-range launch mechanism and a detonating device. The fuse is detonated after the projectile leaves the guide rail and increases the number of revolutions under the action of centrifugal forces. When the M-24F projectile is fired at an elevation angle of 45° and the fuse is set for slow action in the medium density soil, a funnel with a diameter of up to 6 m and a depth of 2.4 m is formed.

Cartridge М-24F M-24FUD
Caliber, mm 240,6 240,6
The length of the projectile with the fuse, mm 1224 1245
Weight of final projectile, kg 112,25 109,4
Weight of explosives, kg 27,4 18,4
Weight of charge, kg 16,2 23,97
Powder charge combustion time at temperatures between -40° and +50° C, s 1—0,5 2,2—0,9
Weight of ignition, kg 0,09 0,150
Length of active section of the trajectory at normal charge temperature, m 90 350
Highest projectile speed, m/s. 280 460
Maximum range of fire (at charge temperatures from - 40 to + 50 ° C), m 6000—7000 10300—11000
Muzzle velocity at charge temperatures from - 40 to + 50°C, m/s 30—45 27—37
Weight of capping, kg 37 37

see. BM-24 Fighting Vehicle