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View Full Version : How to tell if I have a bad barrel ?


sonicbuff
05-18-2009, 12:08 PM
In my life time, I have not gotten a chance to waste a barrel by normal shooting. I'd like to pick your brain in how to identify a bad barrel.

Physically, when you look down a barrel, how do you tell if the barrel is in bad shape ?

MrSlippyFist
05-18-2009, 12:11 PM
Looking down the barrel isn't how I tell, if the barrel has 10's of thousands of rounds thru it and/or is inaccurate as ****, then I know it's bad.

grahlaika
05-18-2009, 12:23 PM
You'll know if your normal 1"-2" groups open up a lot more. Once your target patterns starts to look like a shotgun blast it's probably time to replace your barrel.

sonicbuff
05-18-2009, 1:50 PM
Looking down the barrel isn't how I tell, if the barrel has 10's of thousands of rounds thru it and/or is inaccurate as ****, then I know it's bad.

You'll know if your normal 1"-2" groups open up a lot more. Once your target patterns starts to look like a shotgun blast it's probably time to replace your barrel.

I was at a dealer the other day doing a transfer of an upper, and one of the guy looked down the barrel of my upper, and told me that the barrel is badly shot. I asked him how he could tell that the barrel is in bad shape, he could not explain, but just say that he knows from his experience.

Does this guy know something more than the rest of us ? Or he's just another typical "Saleman" of the year ?

NRAhighpowershooter
05-18-2009, 1:56 PM
I was at a dealer the other day doing a transfer of an upper, and one of the guy looked down the barrel of my upper, and told me that the barrel is badly shot. I asked him how he could tell that the barrel is in bad shape, he could not explain, but just say that he knows from his experience.

Does this guy know something more than the rest of us ? Or he's just another typical "Saleman" of the year ?

if you really know what to look for you can tell if a barrel is almost shot out.. usually by looking at the lands at the throat of the barrel....

J_Rock
05-18-2009, 1:57 PM
I was at a dealer the other day doing a transfer of an upper, and one of the guy looked down the barrel of my upper, and told me that the barrel is badly shot. I asked him how he could tell that the barrel is in bad shape, he could not explain, but just say that he knows from his experience.

Does this guy know something more than the rest of us ? Or he's just another typical "Saleman" of the year ?

More like typical gun store clerk "know it all". If your gun has under 10,000 rounds then its still probably good to go.

sonicbuff
05-18-2009, 2:04 PM
if you really know what to look for you can tell if a barrel is almost shot out.. usually by looking at the lands at the throat of the barrel....

Please explain.

J_Rock
05-18-2009, 2:10 PM
if you really know what to look for you can tell if a barrel is almost shot out.. usually by looking at the lands at the throat of the barrel....

I doubt you can thoroughly examine the throat without a bore scope or gauge to determine how bad the erosion is.

CSDGuy
05-18-2009, 2:26 PM
Well, if your normally rifled barrel now looks like a smoothbore... and shoots like a shotgun, I'd say it's probably gone bad.

sonicbuff
05-18-2009, 2:28 PM
Well, if your normally rifled barrel now looks like a smoothbore... and shoots like a shotgun, I'd say it's probably gone bad.

I guess that's pretty obvious. :p

IsaacGlass
05-18-2009, 2:30 PM
In my opinion when people looks down a barrel, they're only checking to see there's not obvious defectiveness. But to look down a barrel and make such as claim without facts is BS. Which gun shop was this? If you can please pm me so I know not to spend my hard earn $$$ there.

ar15barrels
05-18-2009, 2:35 PM
I doubt you can thoroughly examine the throat without a bore scope or gauge to determine how bad the erosion is.

Don't doubt that.
I do it all the time.

It's quite easy to look down a barrel and see throat wear.
It shows up first as a rounding-off of the lands.
Then the lands start wearing away.

sonicbuff
05-18-2009, 2:43 PM
In my opinion when people looks down a barrel, they're only checking to see there's not obvious defectiveness. But to look down a barrel and make such as claim without facts is BS. Which gun shop was this? If you can please pm me so I know not to spend my hard earn $$$ there.

I really don't want to name the dealer. I guess that the guy just want to throw a sale pitch, convincing me to buy a new upper or barrel.

Personally, I don't think I'm going to bring my business to that place any more.

dieselpower
05-18-2009, 3:14 PM
So when I was told to look closely at the edge of lands and look for rounded not square edges, I was taught right? Look for discoloration inside, chunks of grooves missing (cleaning rod damage). This was correct too?

Just want to know, since I have never seen any of this.

!@#$
05-18-2009, 3:29 PM
Well, if your normally rifled barrel now looks like a smoothbore... and shoots like a shotgun, I'd say it's probably gone bad.

even a smoothbore can get about 6 MOA or better if you can shoot.

sonicbuff
05-18-2009, 3:34 PM
even a smoothbore can get about 6 MOA or better if you can shoot.

My Saiga 12 can get 4 MOA with slug. ;)

CSACANNONEER
05-18-2009, 3:37 PM
You'll know if your normal 1"-2" groups open up a lot more. Once your target patterns starts to look like a shotgun blast it's probably time to replace your barrel.

I had a stock crack once. The barrel was bedded, not free floated, and my groups went from +/- 0.6" @ 77 meters to 8"-12" @ 40 meters. So, I'd suggest looking at the entire gun before assuming that any one component is bad. Also, a barrel can actually shoot its best just before it goes to hell.

ParallaxTactical.com
05-18-2009, 3:40 PM
Lots of good advice here. I'd also say take a look at the crown. It's very important.

Ahhnother8
05-18-2009, 3:54 PM
In my life time, I have not gotten a chance to waste a barrel by normal shooting. I'd like to pick your brain in how to identify a bad barrel.

Physically, when you look down a barrel, how do you tell if the barrel is in bad shape ?

"Bad" is a relative term. You can look down a barrel with or without a borescope and see a washed out throat. But the gun may still shoot, with a change in ammo, particularly with a longer bullet. Or the crown may be damaged, and just needs to be recut. The important thing is if it will shoot to your expectations or not. Barrels are consumable items, just like ammo. Use them up, and put on a new one for another couple of thousand rounds.

Lane

J_Rock
05-18-2009, 6:59 PM
Don't doubt that.
I do it all the time.

It's quite easy to look down a barrel and see throat wear.
It shows up first as a rounding-off of the lands.
Then the lands start wearing away.

Well I stand corrected!

But I still wouldnt trust the guy.

evollep3
09-08-2009, 9:50 AM
Randall do you have any example pictures?