Firearm malfunction

A firearm malfunction is the failure of a firearm to operate as intended for causes other than user error. Malfunctions range from temporary and relatively safe situations, such as a casing that didn't eject, to potentially dangerous occurrences that may permanently damage the gun and cause injury or death. Improper handling of certain types of malfunctions can be very dangerous. The basic rules of firearms safety should be followed at all times to minimize the risk to shooters and bystanders. Proper cleaning and maintenance of a firearm plays a big role in preventing malfunctions.

Case head separation occurs when the walls of the casing become thin or fatigued. Upon firing the round, the case separates into two pieces near the head. It is not uncommon with brass that has been reloaded several times.

A dud (also a misfire or failure to fire) occurs when the trigger is pulled but the primer or powder in the cartridge malfunctions, causing the firearm not to discharge. Dud rounds can still be dangerous and should be deactivated and disposed of properly.

A hang fire (also delayed discharge) is an unexpected delay between the triggering of a firearm and the ignition of the propellant. Whenever a firearm fails to fire, but has not clearly malfunctioned, a hang fire should be suspected. When this occurs, the correct procedure is to keep the firearm pointed downrange or in a safe direction for thirty to sixty seconds, then remove and safely discard the round (which is now a dud as explained above if the primer was struck, otherwise the gun itself may have malfunctioned). The reason for this is that a round functioning outside of the firearm, or in the firearm with the action open (out-of-battery discharge), could cause a serious fragmentation hazard.

A squib load (also squib round, squib, squib fire, insufficient discharge, incomplete discharge) is an extremely dangerous malfunction that happens when a fired projectile does not carry enough force and becomes stuck in the gun barrel instead of exiting it. In the case of semi-automatic or automatic weapons, this can cause subsequent rounds to impact the projectile obstructing the barrel, which can cause a catastrophic failure of the structural integrity of the firearm, posing a threat to the operator or bystanders. The bullet from a squib stuck in the barrel must never be cleared by subsequently attempting to fire a live or blank round into an obstructed barrel. Blank rounds use a type of powder different from that of other rounds, and generate much more pressure, which, combined with the presence of the projectile obstructing the barrel may cause the firearm to fail catastrophically.

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