Check items to add to the cart or select all
4-5. Authorized Rounds
Ammunition authorized for use in the 3.5-Inch Rocket Launchers M20AI and M20A1 Bi is listed in table 4-1. Standard nomenclature, which is used ill the listing, completely identifies the ammunition except for ammunition lot number.
a. Rocket Head.
WP Smoke R locket T127E2 and M30 (T127E3). The head of these rockets is similar in external contour to the head of the HE, AT rocket M28A2. The head is internally threaded at the rear end and contains a 2.33-pound charge of white phosphorus. At the rear it has a union internally threaded to receive the fuze, the burster casing M8 is press fitted into the union, and the steel body fitted over it. The steel ogive and the internal steel dome, which close the forward end of the filler cavity, are attached to the body.
Table 4-1. Authorized Ammunition
Standard nomenclature
Complete round Rocket head Fuze--Standard action nomenclature
Length Weight (in) (lb) Length Weight (in) (lb)
ROCKET, SMOKE, 3.5-INCH: WP, M30(T127E3 or T127E2) 23.55 8.96 10.58 4.47 FUZE, ROCKET, PI-BD: M404A2 or M404A1.
b. Motor Assembly--Pockets M28A2, M29A2, T127E2 and M30 (T127E3).
(1) Description. The rocket motor assembly consists of the motor body, tail assembly, shorting clip assembly, nozzle closure, propelling charge, igniter M20 and M20AI, trap and spacer assembly, and disk and closure assembly. The tail assembly is press fitted over the knurled rear portion of the motor body. The motor body is a steel tube threaded internally at the forward end to receive the disk and closure assembly, constricted to a nozzle internally at the rear and tapered to the knurled surface externally at the rear. The motor body contains the trap and spacer assembly, propelling charge, and igniter. The motor is sealed at the rear by a plastic nozzle closure and at the forward end by the disk and closure assembly. The trap and spacer assembly consists of the disk-like trap to which the spacer blades are fastened and is positioned in the motor lengthwise so that the blades divide the motor chamber into four compartments. The trap is positioned in the rear of the motor to prevent loss of propellant during burning. The motor assembly is threaded externally at the forward end to engage the fuze.
(2) Tail assembly. The tail assembly consists of a cone- shaped aluminum-alloy nozzle extension to which three double bladed fins are crimped or spot welded and three concentric rings are mounted over the fins. The three rings are the grooved support ring, plastic insulator ring, and contact ring assembly (outermost). The rings are held on the fins by rivets which also serve to connect the igniter lead wires to the support ring and contact ring.
(3) Propelling charge. The propelling charge consists of 12 non-perforated cylindrical extruded grains of solvent propellant M7.
A pin holds the sleeve in the retracted position. Upon emergence of the rocket from the launcher, the ejection pin is ejected clear of the fuze by a spring, and the fuze becomes armed. Upon impact, the activating plunger moves forward activating the lever action of the firing pin. This drives the firing pin into the detonator and explodes the rocket.
Preparation for firing. No preparation of the fuze for firing is required other than removal of the
safety band.
d. Fuze, Rocket, Dummy—M405. The dummy fuze M405 is an
inert fuze similar in appearance to the 80 fuze NM404 series described in paragraph c, above. It stimulates the handling and pin ejection of 80 fuze M404 series with a double-locking, bore-riding, round ejection pin and a safety band which is removed prior to firing.
4-7. Preparation for Firing
a. Preparation of Rockets-Rocket. M30 or T127E2. After rockets are removed from their packing’s, they are prepared for firing as follows:
Warning. Examine the launcher to make sure that the safety switch of the trigger grip on the electrical firing mechanism is in a "SAFE" position (fig. 2-1).
(1) All 3.5-Inch Rockets WP Smoke Rockets T127E2 and WP Smoke Rockets M30 (1127E3) should be examined for loose heads. Examine for a discernible 3600 gap between the head and the fuze.
Warning. Any round which has a discernible 3600 gap between the head and the fuze is not to be fired. Any rocket evidencing this condition will be returned to segregated ammunition storage in a properly marked container indicating the condition.
(2) Check rocket for loose nozzle closure by gently pulling the red and green ignition lead wires that pass through the closure. Any movement of the closure indicates failure of bond.
Reference: TM 9-1055201-12
Ammunition authorized for use in the 3.5-Inch Rocket Launchers M20AI and M20A1 Bi is listed in table 4-1. Standard nomenclature, which is used ill the listing, completely identifies the ammunition except for ammunition lot number.
a. Rocket Head.
WP Smoke R locket T127E2 and M30 (T127E3). The head of these rockets is similar in external contour to the head of the HE, AT rocket M28A2. The head is internally threaded at the rear end and contains a 2.33-pound charge of white phosphorus. At the rear it has a union internally threaded to receive the fuze, the burster casing M8 is press fitted into the union, and the steel body fitted over it. The steel ogive and the internal steel dome, which close the forward end of the filler cavity, are attached to the body.
Table 4-1. Authorized Ammunition
Standard nomenclature
Complete round Rocket head Fuze--Standard action nomenclature
Length Weight (in) (lb) Length Weight (in) (lb)
ROCKET, SMOKE, 3.5-INCH: WP, M30(T127E3 or T127E2) 23.55 8.96 10.58 4.47 FUZE, ROCKET, PI-BD: M404A2 or M404A1.
b. Motor Assembly--Pockets M28A2, M29A2, T127E2 and M30 (T127E3).
(1) Description. The rocket motor assembly consists of the motor body, tail assembly, shorting clip assembly, nozzle closure, propelling charge, igniter M20 and M20AI, trap and spacer assembly, and disk and closure assembly. The tail assembly is press fitted over the knurled rear portion of the motor body. The motor body is a steel tube threaded internally at the forward end to receive the disk and closure assembly, constricted to a nozzle internally at the rear and tapered to the knurled surface externally at the rear. The motor body contains the trap and spacer assembly, propelling charge, and igniter. The motor is sealed at the rear by a plastic nozzle closure and at the forward end by the disk and closure assembly. The trap and spacer assembly consists of the disk-like trap to which the spacer blades are fastened and is positioned in the motor lengthwise so that the blades divide the motor chamber into four compartments. The trap is positioned in the rear of the motor to prevent loss of propellant during burning. The motor assembly is threaded externally at the forward end to engage the fuze.
(2) Tail assembly. The tail assembly consists of a cone- shaped aluminum-alloy nozzle extension to which three double bladed fins are crimped or spot welded and three concentric rings are mounted over the fins. The three rings are the grooved support ring, plastic insulator ring, and contact ring assembly (outermost). The rings are held on the fins by rivets which also serve to connect the igniter lead wires to the support ring and contact ring.
(3) Propelling charge. The propelling charge consists of 12 non-perforated cylindrical extruded grains of solvent propellant M7.
A pin holds the sleeve in the retracted position. Upon emergence of the rocket from the launcher, the ejection pin is ejected clear of the fuze by a spring, and the fuze becomes armed. Upon impact, the activating plunger moves forward activating the lever action of the firing pin. This drives the firing pin into the detonator and explodes the rocket.
Preparation for firing. No preparation of the fuze for firing is required other than removal of the
safety band.
d. Fuze, Rocket, Dummy—M405. The dummy fuze M405 is an
inert fuze similar in appearance to the 80 fuze NM404 series described in paragraph c, above. It stimulates the handling and pin ejection of 80 fuze M404 series with a double-locking, bore-riding, round ejection pin and a safety band which is removed prior to firing.
4-7. Preparation for Firing
a. Preparation of Rockets-Rocket. M30 or T127E2. After rockets are removed from their packing’s, they are prepared for firing as follows:
Warning. Examine the launcher to make sure that the safety switch of the trigger grip on the electrical firing mechanism is in a "SAFE" position (fig. 2-1).
(1) All 3.5-Inch Rockets WP Smoke Rockets T127E2 and WP Smoke Rockets M30 (1127E3) should be examined for loose heads. Examine for a discernible 3600 gap between the head and the fuze.
Warning. Any round which has a discernible 3600 gap between the head and the fuze is not to be fired. Any rocket evidencing this condition will be returned to segregated ammunition storage in a properly marked container indicating the condition.
(2) Check rocket for loose nozzle closure by gently pulling the red and green ignition lead wires that pass through the closure. Any movement of the closure indicates failure of bond.
Reference: TM 9-1055201-12