Bulged Barrel?

[ryan42]

This is my second glock.Its a glock 21 45 acp.I shoot 230grain fmj reloads through it.I use tightgroup at 4.5 grains for target.Last week I shot 8 rounds out of the clip and the 8th round got jammed.I tried to clear it but I couldnt pull the slide back all the way.It seems the barrel is bulged.I was wondering what some of you guys opinion would cause this.Thanks

[aa1911]

the barrel is bulged? ouch, was there a squib load where a round got stuck? seems the only possibility. are you able to pull the slide off? if you can get the slide off, the barrel will come right out so you can inspect.

I use that load also, titegroup is a favorite although I don't have any .45 glocks, just my 1911's.

[jack404]

whats the wall thickness of the barrel ??

folks hereb have had a couple bulged barrels too and i cant see any sign of squibbing

theres a impact mark or similar in the barrel if there was

that sort of impact will mark barrels

if no show i'm suss ..

and why i'm asking about thickness

[Jim K]

Obviously a squib load that leaves a bullet in the barrel will cause a bulged barrel if a round is fired behind it. But I have seen a couple of bulged barrels that I think were caused by another problem.

Ryan, can you provide the exact sequence of events that led up to the bulging. Did you have any failure to feed or failure to fire on the preceding round? Any odd sounding shot, like a pop instead of a bang.

Jim

[76Highboy]

Ouch,,, gunsmith time. I would venture to guess a dud but, there is a chance that some previous owner had a dud, hurt the barrel and then you began shooting and had this result. Did you inspect the barrel at all before this. This is one reason I always inspect the barrel of each gun I purchase.

Ryan, before the gun jammed did you hear all the bullets fire and did you see where all of your bullets went? In another words is there a chance it was a dud and you can not verify there was a live round.

[aa1911]

well, if nothing else, you could always get a Lone Wolf replacement barrel or other aftermarket one. Heck, even a new factory barrel isn't too aweful bad, roughly $100 as long as nothing else is messed up, minor to no fitting needed.

[ryan42]

Originally Posted by Jim K

Obviously a squib load that leaves a bullet in the barrel will cause a bulged barrel if a round is fired behind it. But I have seen a couple of bulged barrels that I think were caused by another problem.

Ryan, can you provide the exact sequence of events that led up to the bulging. Did you have any failure to feed or failure to fire on the preceding round? Any odd sounding shot, like a pop instead of a bang.

Jim

Jim every round went of perfectly.How I new i didnt have a squib is that we were plinking around and I was shooting in the water of a pond.Everything went off perfect but when I went to shoot the 8th time and the slide stuck about half way back just enough to remove the jammed casing.I removed the slide and inspected and didnt see the bulge at the time.But when I put it back together same problem I couldnt rack the slide all the way back to chamber another round.When I took the gun in today imediately the guy said the barrel is buldged and when he removed it sure enough buldged right in the middle.Jack I cant measure the thickness of the barrel because the gunshop has it awaiting parts.

[jack404]

ok get the barrel back when they replace it then measure it where it aint bulged i'll work it out from there

[ryan42]

Originally Posted by jack404

ok get the barrel back when they replace it then measure it where it aint bulged i'll work it out from there

ok Jack thanks,if I caused it I just want to know why so it dont happen again.They ordered me a brand new barrel.

[JLA]

Had to have been an obstruction.

[76Highboy]

Originally Posted by JLA

Had to have been an obstruction.

Ya, that is my thought.

[ryan42]

Originally Posted by JLA

Had to have been an obstruction.

Very possible I guess but I sure didnt know it.

[JLA]

It doesnt take very much of an obstruction. Excess oil can even do it..

[CCHolderinMaine]

Originally Posted by JLA

It doesnt take very much of an obstruction. Excess oil can even do it..

Really? I always wonder what the story is with the gun torture tests that pull them out of mud or peanut butter or some other crazy substance, shake it off, work the action a couple times, and then empty a mag.? The poster here might've toasted his barrel by something as simple as overzealous lubrication. Yet a mud puddle poses no threat? When I bought my Mosin, I cleaned the cosmoline pretty well, but in no way did I think I could possibly pop the barrel by not perfectly removing all of it?

[JLA]

Mud can do it and does. A bulged barrel will still fire a bullet. And some do it quite accurately I had a .357 that i bulged and shot for a month before I noticed, and only noticed while I was cleaning it. Only reason it stopped the weapon in Ryans case is because it was bad enough to lock the slide. Had it not bulged enough to stop the slide from operating id wager hed still be shootig today and not know his barrel was bulged.

[76Highboy]

Originally Posted by CCHolderinMaine

Really? I always wonder what the story is with the gun torture tests that pull them out of mud or peanut butter or some other crazy substance, shake it off, work the action a couple times, and then empty a mag.? The poster here might've toasted his barrel by something as simple as overzealous lubrication. Yet a mud puddle poses no threat? When I bought my Mosin, I cleaned the cosmoline pretty well, but in no way did I think I could possibly pop the barrel by not perfectly removing all of it?

It is all in perspective. I just had a revolver where I stuck 3 bullets into the barrel with no damage and had to drill them out, and then I have seen shotguns explode due to mud in the barrel. Then, I have read where barrels have been damaged due to over oiling and then trying to fire them. It would be nice to know what caused the barrel to bulge.

[JLA]

Yep too many variables. Hes shooting .45 ACP so pressure isnt likely a cause. Due to the low pressure and low velocity of the .45 ACP that all but rules out partial obstruction like too much oil. In my mind the only real possibility here is a stuck bullet.. Perhaps a bridged powder dump from the measure and the round that stuck only got a half grain of titegroup or so. Which means there could be a round in the rest of the loaded ammo with a near double charge.. Or best case scenario.. A round simply didnt get charged with powder and the primer just pushed the bullet an inch or so down the barrel where the next round fired normally collided with the stuck bullet and both went on to the target..

[ryan42]

Originally Posted by JLA

Mud can do it and does. A bulged barrel will still fire a bullet. And some do it quite accurately I had a .357 that i bulged and shot for a month before I noticed, and only noticed while I was cleaning it. Only reason it stopped the weapon in Ryans case is because it was bad enough to lock the slide. Had it not bulged enough to stop the slide from operating id wager hed still be shootig today and not know his barrel was bulged.

Im sure your right.

[CCHolderinMaine]

Originally Posted by JLA

Yep too many variables. Hes shooting .45 ACP so pressure isnt likely a cause. Due to the low pressure and low velocity of the .45 ACP that all but rules out partial obstruction like too much oil. In my mind the only real possibility here is a stuck bullet.. Perhaps a bridged powder dump from the measure and the round that stuck only got a half grain of titegroup or so. Which means there could be a round in the rest of the loaded ammo with a near double charge.. Or best case scenario.. A round simply didnt get charged with powder and the primer just pushed the bullet an inch or so down the barrel where the next round fired normally collided with the stuck bullet and both went on to the target..

Care to throw a number at the % of the time a bullet stuck in the barrel will be "pushed" out by the next round verses exploding barrel syndrome?

[76Highboy]

Originally Posted by CCHolderinMaine

Care to throw a number at the % of the time a bullet stuck in the barrel will be "pushed" out by the next round verses exploding barrel syndrome?

Your analysis is kind of why I think that someone stuck two bullets in the barrel and caused the barrel to bulge and got rid of it. Then Ryan gets the gun and the continued use causes the barrel to begin distorting just enough to cause the slide to jam against it. That is what comes to mind with me. Past that, I am clueless. As far as one bullet knocking the first one out I am not sure about that and have never heard of it happening.

[Jim K]

The actual cause of a bulged barrel is often misunderstood. It is heat. When the bullet begins to move, it rapidly picks up a lot of kinetic energy. When the bullet is stopped abruptly, that energy is dumped in the form of heat. That heat softens the steel of the barrel and the normal pressure bulges or breaks the softened steel.

If the bullet is not stopped, or slows to a stop, the energy dump is not as abrupt and the heat has a chance to dissipate. That is the case with a soft material in the barrel (peanut butter?) or with something like rainwater, which does not slow the bullet significantly. But if the front bullet is at the rear, so the second bullet is touching it, the second will not be stopped, and the two bullets will exit as one, at effectively double the mass. The pressure will be higher than normal, but the the barrel will not bulge.

Also, if a bullet is stuck in the barrel and a round without a bullet is fired, the powder gas alone does not have enough kinetic energy and is not stopped abruptly enough to cause a bulge. In fact (dirty little gunsmith secret) a common way of removing barrel obstructions like broken bore snakes is to use a half charge of powder without a bullet and simply shoot them out.

Jim

[dcriner]

Jim, I'm trying to reconcile that versus a muzzleloader with the ball not rammed tight against the powder charge, leaving a vacant space behind the ball. Supposedly, that will increase the pressure and somehow damage the bbl.

[CCHolderinMaine]

Also, if a bullet is stuck in the barrel and a round without a bullet is fired, the powder gas alone does not have enough kinetic energy and is not stopped abruptly enough to cause a bulge. In fact (dirty little gunsmith secret) a common way of removing barrel obstructions like broken bore snakes is to use a half charge of powder without a bullet and simply shoot them out.

Thank you for that answer, that's a question I've wondered. So what you're saying is; even if I cemented shut the end of a barrel with something completely immovable, even if I fired a full normal powder charge(no projectile), the barrel should not be damaged.

[jaydub]

All my Glocks have after market barrels. I highly recommend this as the way to go.

[Jim K]

Hi, dcriner. I have heard that time and again, but I tried it and nothing happened except the bullet blew out. I have even challenged one fellow to prove to me that it can happen and offered to pay for the rifle if the barrel burst or bulged. He refused, but kept insisting that he read that someone said that maybe it happened to a cousin.... You get the picture.

Hi, CC holder. Well I have never tried cementing the barrel shut, but I think the answer would be that with no bullet the plug would just be blown out. Now if a bullet were fired, the precursor wave would probably blow out the plug. But if it didn't, and the bullet stopped, the muzzle would be opened up the same as when a rifle is fired with mud in the barrel. Those kinds of obstructions usually result in the barrel splitting along the fault lines (that is the rifling) and the barrel opens up in a nice flower pattern.

Of course, you made your plug immovable. What would happen is just that the pressure would build up as the powder burned. If the barrel were weak, it could burst, but with a normal barrel that gas would be contained. The pressure would be lower than normal chamber pressure since the gas would have much more room for expansion than in just the chamber.

Jim