I.B. 4-lb. Mk IV, IVE, V, VE, and 4-lb. "X" wiih 2- and 4-minute delays, Mk Il (Service)
No Image Available Filler and Weight
NA,
Body and Overall Weight
NA, 4 lb.
Color
Bright Red
Type of Round, DODIC
I.Bi,Mk Iii, NA
Description:
The Bomb Mk IV is hexagonal in shape, having a hollow magnesium-alloy body, and a cast iron nose, with the body cast to the nose in manufacture. A tin-place tail, closed by a tail cover, is secured to the other end of the body by three drive-screws, which also hold a steel striker housing in position in the body. At the tail end, the body is counter-bored to accommodate an igniting mechanism consisting of a striker, located in the striker ho using, and a steel plate seated at the bottom of the counter-bore and containing- a 1.7-gram detonator. One end of the striker is pointed, and the other end projects through a hole in the striker housing. The edge of this hole in chamfered to permit a thin brass cross, secured to the striker, to be bent and pulled through the hole when the bomb functions. This cross forms a striker support during transit and storage. Movement of the striker towards the detonator is, when the bomb is packed in it; case, prevented by a spring-loaded safety plunger housed in a sleeve. Two vent holes, plugged by cork inserts, are pro¬vided in the tail end of the body and communi¬cate with the space between the igniter mecha¬nism and the bomb main filling. A strip of primed cambric is located in this space. The Mk IVE is identical to the Mk IV except for a black-powder buster charge, just abaft the nose plug in the body cavity, which replaces a small quantity of the termite filler.
Use:
Incendiary bombs of many various types, ranging in weight from 4 to 2o0 lb., are at pres¬ent in service use for operations against dif¬ferent types of targets. The Construction and filling of these bombs differ with the individual types, and no general description can be given here to cover the complete range.
Functioning:
When the bomb is released from the container, (he safety plunger springs out, and, on impact with the target, the striker moves down, breaking free from the brass cross striker support and firing the detonator. The flash from the detonator ignites the primed cambric strip and the priming paste (gunpowder-shellac paste); and the products of combustion blow the cork inserts out of the vent holes. The paste ig¬nites the pressed priming composition which, in turn, ignites the termite pellets. The mag¬nesium-alloy body starts to melt about 25 sec. after the bomb has ignited, and burns for about 10 minutes. In the Mk IVK, after 1 1/2 to 4- minute, the gunpowder in the buster is ignited and explodes.
Munition Components:
  • Fuze Internal simple impact striker
  • Fuze Internal simple impact striker
  • Fuze Internal simple impact striker
Data Source:
OP_1665ExplosiveOrdnanceBritish1946
Munitions Tech Data Sheet:
Back to MOTIS Search Page

UXOInfo.com is brought to you by: