Infantry Drills

H-109: Flexible Linear Charge

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H-109. The simplest field-expedient charge for reducing wooden doors is the flexible linear charge. (See Tables H-3 and H-4 (page H-34) for charge use and system components.) It can be made in almost any length and is easily carried until needed. It is effective against hollow-core, particle-filled, and solid wood doors. When detonated, the flexible linear charge cuts through the door near the hinges.

H-110. To construct the flexible linear charge, lay out a length of double-sided contact tape with the topside adhesive exposed. Place the necessary number of strands of detonation cord down the center of the double-sided tape, pressing them firmly in place. Military detonation cord has 50 grains of explosives per foot and 7,000 grains in a pound. Most residential doors are 80 inches tall. Commercial doors are 84 inches tall. This must be considered when calculating the quantities of explosives, overpressure, and MSDs. For hollow-core doors, use a single strand; for particle-filled doors, use two strands; and for solid wood doors, use three strands. If the door type is unknown, use three strands. One of the strands must be cut about a foot longer than the others and should extend past the end
of the double-sided tape. This forms a pigtail where the initiating system is attached once the charge is in place. Cover the strands of detonation cord and all the exposed portions of the double-sided tape with either sturdy single-sided tape or another length of double-sided tape. Roll the charge, starting at the pigtail, with the double-sided tape surface to be placed against the door on the inside.

H-111. At the breach site, place the charge straight up and down against the door tightly. If it is too short, place it so it covers at least half of the door’s height. Prime and fire the charge from the bottom.

Table H-3. Charges
Table H-3. Charges (continued)
Table H-4. Firing system components

Next: H-112: Explosive Safety Factors

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