CHAPTER 4

PROBLEMS AND DESTRUCTION


     This chapter identifies some of the problems that cause the weapon to

     perform improperly. It also explains how to identify unserviceable

     parts, and how to destroy the M249 when authorized to do so.

4-1. MALFUNCTIONS

A malfunction occurs when a mechanical failure causes the weapon to fire improperly. Defective ammunition or improper operation by the automatic rifleman is not considered a malfunction. If cleaning and or lubricating the weapon does not fix the problem, then it is turned in to the unit armorer. Table 4-1 shows malfunctions, their probable causes, and the corrective actions.

Table 4-1. Malfunctions.

4-2. STOPPAGES

A stoppage is any interruption in the cycle of functioning caused by faulty action of the weapon or faulty ammunition. Stoppages are classified by their relationship to the cycle of functioning. Table 4-2 shows types of interruptions or stoppages, their probable causes, and the corrective actions.

Table 4-2. Stoppages.

Table 4-2. Stoppages (continued).

4-3. IMMEDIATE ACTION

Immediate action is action taken to reduce a stoppage without looking for the cause. Immediate action should be taken in the event of a misfire or a cookoff. A misfire is the failure of a chambered round to fire. Such failure can be due to an ammunition defect or faulty firing mechanism. A cookoff is the firing of a round by the heat of a hot barrel and not by the firing mechanism. Cookoffs can be avoided by applying immediate action within 10 seconds of a failure to fire. The automatic rifleman keeps the AR on his shoulder while performing immediate action procedures. If the M249 stops firing, the following immediate actions are taken. (An effective memory aid is POPP, which stands for Pull, Observe, Push, and Press.)

    a. Pull and lock the cocking handle to the rear while observing the ejection port to see if a cartridge case, belt link, or round is ejected. Ensure that the bolt remains to the rear to prevent double feeding if a round or cartridge case is not ejected.

    b. If a cartridge case, belt link, or a round is ejected, push the cocking handle to its forward position, take aim on the target, and press the trigger. If the weapon does not fire, take remedial action. If a cartridge case, belt link, or round is not ejected, take remedial action.

    DANGER

    If nothing is ejected and the barrel is hot (200 or more rounds fired in less than 2 minutes), do not open the cover. Push the safety to the right (red ring not visible), which places the weapon on safe. Keep the weapon pointed downrange and remain clear for 15 minutes, then clear the weapon.

4-4. REMEDIAL ACTION

Remedial action is any action taken to determine the cause of a stoppage and to restore the weapon to an operational condition. This action is taken only after immediate action did not remedy the problem.

    a. Cold Weapon Procedures. When a stoppage occurs with a cold weapon and immediate action has failed, use the following procedures.

    b. Hot Weapon Procedures. If the stoppage occurs with a hot weapon (200 or more rounds in less than 2 minutes), move the safety to SAFE, wait 5 seconds (during training, let the weapon cool for 15 minutes), use the same procedures as outlined for cold weapon procedures.

    DANGER

    Be careful in clearing the weapon when the barrel is hot, a round may fire (cookoff) from the barrel's heat instead of by the firing mechanism. During combat, wait 5 seconds because of the possibility of a "hangfire" before applying remedial action. During training, wait 15 minutes before clearing a hot weapon and applying remedial action.

4-5. DESTRUCTION PROCEDURES

Destruction of any military weapon is only authorized as a last resort to prevent enemy capture or use. This paragraph discusses the field-expedient means of this destruction; it does not replace published policies. In combat situations, the commander has the authority to destroy weapons, but he must report this destruction through channels.

    a. Disassemble the weapon as completely as time permits. Use the barrel to destroy the bolt, operating rod group, bipod, sights (rear and front), and receiver.

    b. Bury the disassembled weapon or dump the parts into a stream, a sump, or a latrine.

    c. Burn the weapon by placing an incendiary grenade on the receiver group over the bolt (with the cover feed mechanism assembly resting on the grenade) and detonating the grenade.