Ammunition Malfunctions

By lklawson, Oct 24, 2016 | |
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    Ammunition Malfunctions
    by Kirk Lawson

    There are three common ammunition malfunctions with modern self-contained metallic ammunition, inclusive of both center-fire and rim-fire. In this article we will briefly look at what they are and how to deal with them.

    1) Squib Load
    A "Squib Load," or more commonly just a "squib," is a cartridge which develops less than normal expected velocity or pressure. The term most likely stems from a mid-16th Century firework of the same name which made a hissing or small popping noise. Signs of a Squib Load following a trigger press include softer than expected noise, milder than normal recoil, a bullet which can be watched as it travels down range and visibly drops to the ground, hits on target much lower than expected, shots which do not seem to impact the target at all but are coupled with reduced sound or recoil. There may be several causes for a Squib Load but the most common are a cartridge which has been loaded without gunpowder or a cartridge loaded with a dramatically reduced charge of gunpowder. Essentially, only the force of the primer, which is intended to ignite the gunpowder, is forcing the bullet from the cartridge and down the barrel.

    The greatest danger with a Squib Load is that the underpowered cartridge simply doesn't have enough force to push the bullet out of the bore and it becomes stuck inside the barrel, forming an obstruction. If another round is chambered and shot, forcing a second bullet down the barrel, the obstruction will cause dangerous pressure inside the barrel which could damage the barrel and firearm. Shots fired into an obstructed barrel have been known to swell the barrel like a ballon, burst it like a bubble popping, and even peel the end of the barrel back daisy-petal style reminiscent of a Bugs Bunny/Elmer Fudd gag, potentially sending hazardous bits of steel flying about. Adding insult to injury, a shot fired into an obstructed barrel could also cause blow-back back down the barrel towards the shooter which could include searing hot gasses and bits of the cartridge and gun.


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    If you believe you have experienced a Squib Load, STOP FIRING IMMEDIATELY! The steps to address the issue are simple but if you do not feel comfortable or qualified, call for the Range Safety Officer to assist you. First, after you stop firing, unload your gun and clear the chamber. Make sure there is no live ammunition in the gun at all. Then open the action and disassemble the gun as much as safely possible with the object of removing the barrel if possible. Use a cleaning rod or a brass or aluminum rod to check the entire length of the barrel for obstructions. If there is an obstruction found, use the rod to tap it out. You may need to tap it out from either direction depending on how far down the barrel it has traveled. Once the obstruction is cleared, carefully examine the gun for damage or obviously broken parts then reassemble the gun. Visually inspect the rest of the ammunition from the same manufacturing lot, checking for defects. Some shooters will go so far as to use a sensitive scale to weigh each cartridge with the goal of ensuring that an equal charge of gunpowder is in all. Once you are confident that the gun is in good working condition and there are no obvious defects with the ammunition, you can load the firearm and return to shooting, often within the space of a few minutes.

    2) Hangfire
    A Hangfire is a perceptible delay of the ignition of the cartridge after the trigger has been pressed. Signs of a hangfire are you press the trigger, then... nothing for a short bit then BANG!, the round ignites, sending a bullet down the barrel. Always keep the firearm pointed in a safe direction for up to 30 seconds until the round fires. Hangfires are often caused by a defective primer but may also be caused by defective gunpowder which, for various reasons, may experience a delay igniting. If you experience a hangfire, unload the gun and carefully inspect the remaining ammunition obvious defects. If there are no obvious defects with the ammunition, you can return to firing. However, pay particular attention to the firing sequence. If more ammunition malfunctions occur with that lot, discontinue using it and dispose of it safely.

    3) Misfire
    A Misfire, sometimes called a "dud," is a cartridge which completely fails to fire after being struck with the firing pin. The indications of a Misfire are that you pull the trigger and hear the "click" of the firing pin hitting the primer and then just nothing. Misfires are the result of a failure of the primer to ignite. There are three common causes for misfires. First, the primer itself may be defective and incapable of igniting. This is especially common with inexpensive rim-fire ammunition which often has dead-spots or completely defective priming in the rim.

    The following two reasons are related in that the primer itself is not technically defective however, the firing pin is simply not impacting with enough force to set it off. The first of those to may be that the cup of the primer, the metal from which it is made, is "hard" or too thick for the force of the gun's firing pin to sufficiently dent it. This is may be because the primer is simply of a harder or thicker material, sometimes intended for a different type of gun. Some brands of primer are noted for being "harder" and some ammunition is intended for use in guns, such as sub-machine guns, commonly accepted to have more energetic firing pin hits. If this is the case, a second strike on the primer by the firing pin (pulling the trigger again) will sometimes fire the cartridge. Another reason that a primer may be too "hard" or the material too thick is if the wrong primer was used for the cartridge. Usually, this takes the form of a primer designed for a rifle being used to manufacture a pistol cartridge. Rifle primer cups are thicker because they must withstand the typically higher pressures generated by rifle cartridges. This is a mistake of manufacture which, though rare in any case, seems to be more common of hand-loaded than factory ammunition. The second reason that the firing pin may have not struck the primer with sufficient force is a problem with the gun. There may be a defect or a broken or worn part which is causing the firing pin to have less force than the designer intended. Damaged firing pins, firing pin channels fouled with grime from shooting, or weakened firing pin/hammer springs are often the cause of this. In both of these last two cases, too little force from the firing pin or too hard/thick primer cup, the cartridge is still technically "good" and WILL FIRE if the primer is struck with sufficient force. When this happens it is called a "Light Strike." Light Strikes may be identified by comparing the primer of the round which failed to fire with others which have. If the impression on the unfired round is obviously more shallow, then it is likely that the cause is a Light Strike.

    While also rare, firing pins can sometimes be bent and may not be striking the primer near enough to its center, or even at all. Once again, examination of the cartridge can help identify this problem.

    If you experience a Misfire, stop firing and KEEP THE FIREARM POINTED IN A SAFE DIRECTION, usually down range. You do not know yet if the "click" is because of a Misfire or because of a Hangfire. Keep the gun pointed in a safe direction for a full 30 seconds. Count it off out loud. If the round has not ignited after 30 seconds, it is very unlikely to be a Hangfire. You may elect to try a second strike or eject the round and examine it. You may need to clean or repair your gun. Examine the ammunition and gun for fouling, wear, or damage. Follow the firearm manufacturer's recommendation for maintenance, including changing springs.

    If a batch of ammunition consistently fails to fire, stop using that lot and safely dispose of the ammunition.

    While these ammunition malfunctions are fairly uncommon, they do occur often enough that a firearms owner needs to know what they are, what causes them, and how to address them when they do happen.

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