What causes a gun to jam?

Question

I had several pistols jam on me at the range the other day (I'm a novice), and I had to manually pull the slide back to get them firing again.

What causes this kind of jam?

What can one do to minimize such occurences?

What can one do to fix a jam, other than manually pulling the slide back?

Thanks!

Answer 1

When people refer to a gun jamming, they are describing several possible stoppages:
First, a gun may fail to feed. This usually indicates a defective magazine, but it could also be caused by trying to feed hollow points or semi-wadcutter bullets in a pistol not designed to fire other than round nosed hardball.
Next, a pistol my fail to eject. This is usually caused by weak ammo which does not produce enough recoil impulse to push the slide all the way to the rear. It can also be caused by firing a pistol with a "limp wrist" grip. If the weapon is not held firmly, the entire weapon recoils back, not allowing the slide to complete its backward movement.
Finally, the pistol may fail to eject. This could be caused by a faulty ejector (the little piece of metal that strikes the casing as the slide travels rearward). Usually, it is caused by a defective extractor, the little hook that holds the casing against the face of the slide. It the extractor does not hold the casing tightly, when it hits the ejector, it spins around and gets stuck between the face of the slide and the barrel. Then the mouth of the casing points upward, this is referred to as a "stovepipe".

Answer 2

The gun may be dirty, it may have a defective magazine which is quiet common, you may have some crappy ammo. The recoil spring may need replacing. The operating rod in the gas system may be damaged or bent. The extractor may be broken or otherwise damaged. The chamber could be rusted or just rough. Your question was a little vague and so I don't know what kind of jam your having, The first thing is to strip and clean the gun thoroughly. The trigger group should come out as an assembly, Do Not Disassemble the trigger group, just spray the gunk out of it with some brake parts cleaner and let dry, then oil lightly. Make sure you remove the operating rod and gas piston then clean the tube well ,I like to blow thru it with compressed air to assure the gas bleed hole is clear into the guns bore, just be sure no small parts remain inside because the compressed air will send them flying. Clean the bolt and the receiver of all built up gunk, then lightly oil. Reassemble and try the gun, if it still malfunctions get another magazine. If this doesn't help take it to a gunsmith.

Answer 3

The jam that you are describing is called a "stove pipe" jam because the shell gets caught in the slide and sticks up like a stove pipe. The most frequent cause for this type of jam is failure to lock your wrist when you are firing. This allows a major part of the recoil to be lost in throwing your wrist back. This robs power from the slide and, consequently, causes the shell to be only partially ejected. The solution to this problem is to be sure that your wrist is locked (held in a stiff position) when you fire the gun. If you are unable to hold the gun so that it doesn't cause your wrist to flex when the gun fires, you may need to go to a less powerful caliber while you learn the proper way to fire a semi-auto handgun. Once you have mastered the proper way to hold the gun when firing it, you can move to the larger calibers.

There is a procedure for handling these jams in the field. It is called the "Rap, Rack and Return" drill. The procedure is to first "Rap" or use the heel of your off hand (the left hand if you are right handed) to strike the bottom of the magazine. This is done to ensure that the magazine has been completely inserted. Next you "Rack" or pull back the slide and release it. This releases the jammed shell and allows a fresh round to be chambered. Then you "Return" the gun to the firing position and prepare to fire the next round. Properly performed, this procedure can be easily done in less than two seconds. Another less popular procedure to quickly get your gun back into action is to use your off hand to quickly swipe from in front of the slide toward the rear sight in order to knock the jammed shell from where it is being held in the partially closed slide. This procedure assumes that a fresh round has been picked up by the slide but the spent shell has been caught by the closing slide. This may not be the truth and such a procedure could cost you precious seconds when you can ill afford them because you could find that you still need to perform the "Rap, Rack and Return" drill before your gun will return to battery. Check with the folks at the gun range where you go and ask them if there is anyone who gives classes on handguns.

Answer 4

I took the time to read most of the above answers and I must tell that alot of people answer here for points, and they have no clue.

90% of auto feed gun jambs are from the clips. Clips gather everything from dirt to spent powder. They also get bent at the feeding ramp. All of this is fixable by either replacing the clip with a new quality clip, or cleaning it inside and out. If you are using clip bought from a gun show or surplus then most likely that is your issue. It seems strange to have so many jamb on a single day. That being the case I would say you have 1 of 2 issues.

1. You have buildup or dirt in the firearm which will cause issues. Clean it and go again. I seen alot of people say this and its very true. Some guns can take the dirt, others cant. This is usually a by product of the price you paid for the gun !

2. You have a gun or guns that are known to jamb. No one likes to hear their gun is cheap. The fact is the reason why H&K, Sig, Glock, etc. are so pricey is because of the the quality. Known guns that jamb ( Handguns ) are less pricey but you have to deal with what you get. Those names include the ever so popular Ruger handguns. Smith & Wesson Sigma series. Taurus and the Highly claimed Beretta are all guns that are known to jamb either from poor quality or simply cant take much dirt to cause issues. There are many rifle and shotguns on that list aswell. Ramp wear causing jambs is very rare. Cheap ammo causing them is even more rare.

The worst thing I seen said was the holding of the gun. This is a myth and I will be happy to demonstrate that no matter how the gun is held it will fire given its prop. working. Much like "Dont Dry Fire your gun" this is nothing more than rumors for todays modern guns. I have even heard the local police talk about this, and how they were instructed and that it does matter. After a short demo with the department, they no longer believe the hype.

Whatever your issue, dont let it get you down. Happy shooting !!!!!

Answer 5

In order of probability:

1. Not clean
2. Cheap or poorly re-loaded ammo, or wrong bullet type.
3. Poor grip.
4. Gun in need of repair (usually the extractor)
5. Cheap gun.

To minimize: proper cleaning and maintenance, use good quality ammo. Use a solid grip.

To fix: Pull the slide back. Shake out the jammed case. Sometimes you have to go as far as unloading and manually fixing the jam.


Edit::::
The Mrs. below has a good point.
Clips are another culprit. Often, the difference between a bad clip and a good one is a fraction of a millimeter bend in the feed lips.

Answer 6

A gun has to be held firm to allow it to cycle properly. Many novices hold the gun too loosely. Since it was several guns that had problems I bet it is your grip.
Use both hands to steady yourself, a rest aids in accuracy but some people relax their grip when they use one.
If it jams all you can do is cycle it manually.

Answer 7

First off there are several causes for that but the most common one is simple a dirty gun. clean your guns thoroughly. There can also be week powder Charge or defective ammo. If you reload don't forget to take measurements. Beyond that I don't have your firearms in front of me or I could give you a more accurate diagnosis. But I reiterate clean your gun. Its been my experience 85% of the time that a guns simply dirty fore example In automatic pistil unburnt Powder will gunk up the slide. Besides a dirty gun change your ammo your shooting.

Answer 8

Cheap ammo can do it, but if you're a novice, chances are you aren't holding the gun properly. You need to keep your shooting arm straight so the gun doesn't move back. The pressure you hold against the gun is used to exert enough pressure to kick in the next load. Have someone at the range help you with your stance and hold. have fun.

Answer 9

Some jam because they are dirty. Regular cleaning after every use is needed for proper maintenance. Old ammo can also cause your firearm to jam. If it is over a year old, dispose of it properly. If these things don't work you may need to have te spring that loads the ammo replaced.

Answer 10

Could be that you're not holding the gun properly.

Could be that the rails that guide the slide need some light lubricant.

Could be that you are using cheap ammunition. The aluminum jacked ammunition is junk, and will jam a lot.