TM-9-2350-311-10

TM 9-2350-311-10

2–12 PREPARATION FOR FIRING — CONTINUED

2–1 2.5

Loading the 155MM Cannon — Continued

b. Power Ramming — Continued

To prevent injury to personnel, stand clear of breechblock. Do not close breechblock unless red

igniter pad is visible.

Cannoneer no. 1 commands “CLOSE” and lifts operating cam (7).

After breechblock (2) is closed, cannoneer no. 1 ensures that witness marks (18 and 19) are alined. If

witness marks are not alined, do the following.

(a) Release operating handle (3) and push in clutch pin (20).

(b) Hold clutch pin (20) in and push forward on operating handle (3). this should rotate breechblock (2)

closed.

•

if breechlock does not lock, do not load primer to prevent injury to personnel. Report

unsafe condition to supervising officer and unit maintenance, then unload cannon assembly

(para 2–14).

•

NEVER insert primer in primer chamber unless breechblock assembly is closed and locked.

Ignition of propelling charge with breechblock not fully closed presents a critical hazard to

crew.

•

Don’t force primer into primer chamber, Forcing primer could prematurely

charge causing the howitzer to recoil resulting in serious injury to the crew.

NOTE

Use only M82 primer in cannon assembly (para 5-2.4).

ignite powder

Cannoneer no. 1 inserts primer (21) into primer chamber, If primer will not go in, primer chamber is

probably dirty. Clean primer chamber and vent hole by inserting reamer assembly into chamber as far as

it will go and rotating briskly. After primer is inserted, cannoneer no. 1 announces, “PRIMED.”

2-210

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