Bulged barrel in a semi-auto - unsafe?

[tacotime]

Just saw a friend's 4516-1 which looks like new, but on closer inspection has a bulge in the barrel. It's about an inch forward of the start of the rifling. Easily seen as a dark ring looking down the clean barrel into light, not obvious from the outside, but can be detected though not immediately obvious, if running fingers on the outside of the barrel. No cracks seen.

Do we expect this barrel is safe to use with standard factory loads?

Will a bulged barrel get worse over time with
factory loads?

If you get a bulged barrel in a gun like the 4516, do we expect any other parts to be damaged?

Thanks!

 

[tacotime]

Just saw a friend's 4516-1 which looks like new, but on closer inspection has a bulge in the barrel. It's about an inch forward of the start of the rifling. Easily seen as a dark ring looking down the clean barrel into light, not obvious from the outside, but can be detected though not immediately obvious, if running fingers on the outside of the barrel. No cracks seen.

Do we expect this barrel is safe to use with standard factory loads?

Will a bulged barrel get worse over time with
factory loads?

If you get a bulged barrel in a gun like the 4516, do we expect any other parts to be damaged?

Thanks!

 

[john traveler]

A bulged barrel absolutely should be replaced. It is not safe to continue firing with standard or other loads.

In theory, a recoil-operated pistol will not cycle the slide with a bullet lodged in the bore, but don't count on it! I've inspected several blown-up pistols that got that way from firing with a bore obstruction.

The problem with a bulged barrel is that propellant blow-by gas escapes at the bulge, greatly increasing the chance of a bullet stuck in the bore. In a blow-back operated pistol, this commonly cycles the slide, chambering another round and setting the stage for a gun blowup. In recoil-operated guns, a minimum energy is needed to cycle the slide and have it chamber a second round. Whether by self-cyling, or deliberate racking of the slide, firing a gun with a bore obstuction is guaranteed to ruin the gun, and very likely the shooter too. Damage could include warping of the slide lockup area, failure to effect disassembly, or blown magazine, extractor, etc.

 

[Gun 4 Fun]

This is what happens when a bullet gets stuck in the bore. This is a stainless steel Wilson match barrel that cost me $100 20 years ago to buy and have fitted. The load was a light target load with a 200 H&G no. 68 semi-wadcutter. I don't remember the exact charge, but the powder was Win 452AA, with a standard pistol primer. I had a squib load, but there was enough energy in the load to stick the bullet halfway down the bore and still cycle the action and chamber another round. The gun is a highly customized Springfield Armory 1911A1. If you look closely, you can see the split runs from end to end, right through the recoil lug and throat. The bulge isn't that bad, but can be seen plain as day when looking through the bore. The round that fired after the one that stuck, caused the bulge, when it slammed into the rear of the stuck bullet. Still, it pushed both on out, and a couple more were fired through the barrel. It happened during a rapid fire string in a match, and since it cycled, I didn't quite realize what was wrong. I couldn't tell any difference in the sound with muffs on, and several other guys firing a few feet away. My spotter didn't notice either. Not until I stopped to check out why I was getting hit in the face all of a sudden by gas and particles

 

[john traveler]

Lucky those were mild 200 grain SWC loads.

Full-power FMJ ball would have greatly bulged the barrel, and probably ruined the slide too.

 

[tacotime]

Thanks Gents. A new barrel has been ordered as the gunsmith agreed! No since taking more of a chance with every shot and wondering about the risk from now on.


Taco

 

[bountyhunter]

Originally posted by john traveler:
A bulged barrel absolutely should be replaced. It is not safe to continue firing with standard or other loads.

+1000

 

[Deltaboy]

Originally posted by bountyhunter:

Originally posted by john traveler:
A bulged barrel absolutely should be replaced. It is not safe to continue firing with standard or other loads.

+1000

I second that +1000