Odd Cracks in Barrel

[gunsandgunsmithing]

Not cracks!

 

[Brians356]

We see this quite a bit, it's simply corrosion from moisture in the bore.
Later, Mark Buettgen
Bartlein Barrels Inc.

How deep, in your estimable estimation, are the "channels" we see?
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[gunsandgunsmithing]

Try cleaning it and not putting it away dirty

 

[Ggmac]

Do you live in a high humidity area ? Shooting the rifle (then not starting the cleaning regime at the range while the barrel is warm ) then placing it in a case then into an AC car ride will create moisture in the barrel .
Living in s Florida, ive learned to start the cleaning process while at the range then clean as soon as I get home . Condensation will start also when going from a warm hose to a cold car ride to the range .

 

[Mark Buettgen]

How deep, in your estimable estimation, are the "channels" we see?
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It depends on the extent of the damage. It can be .001" to .002" or we've seen as deep as .005" and rare cases more. Land heights are generally .003" to .004" high and we've seen them cut completely across and into the groove in more serious cases.
There are some water based cleaners, while very good products, should not be left in the bore for extended times. Always patch dry and then coat with a protective product, I use an oil.
Bores left dirty seem to attract and hold moisture.
I clean after every range session
Later, Mark

 

[SBS]

I see a lot of this on hunters' rifles. Usually worst at the muzzle and gradually goes down the barrel until it reaches the half way point many times. These barrels are seldom worn out at the throat, but pitted from neglect by hunters who are out in the elements and either seldom clean or think a patch or 2 at the end of the season is sufficient. In the case of hunting rifles, I suspect the main cause is cold damp weather and the resulting condensation when taken in a warm car, tent or building and not dried out and cleaned right away. The usual complaint is that the rifle isn't accurate anymore.

 

[B muzguy]

No

I don’t know I think it’s a defect I have I Compass lake engineering Krieger barrel that has those warm holes. Does not hurt accuracy one bit that I can tell. also have six other match grade barrels . All rifles have been treated the same and I have two barrels that have been shot out and they are laying under my bed for three years without any oil in them and they have no warm holes at all so it is not neglect in my opinion. I am no expert I just believe that the barrels have defects in them . And should have been borescope before sent out door.

 

[B muzguy]

Looks like some impurities that cooked off or cooked out or crystallized during heat treatment???

 

[B muzguy]

Be easy to find out just re-bore to a bigger caliber and see if there is any worm holes

 

[snert]

Several of my barrels have them too...a Hart from the PJ era, with only a few rounds thru it, and an old 1950s CM barrel that had pits in it so deep lands were gone. The shape of the pits was just like those worm marks.

The great news is both barrels shoot/shot great, even when the CM barrel really only had 4 inches of decent rifling.