Gunsmithing Borescope question

[IDbound]

I don't think I have seen a post on this subject for 2 days so I figured I may as well ask so as to get my ridiculement for the day. I am assuming the black marks (in the form of a triangle) that are evident at the beginning of my lands is just the beginning of the onset of barrel erosion after 3-400 rounds?

 

[6.5SH]

Assuming the top of the pic is the chamber end that looks like the leade.

 

[FredHammer]

Technically, every round is causing erosion, but that erosion doesn't have ill effect until way down the road of round count. You are most likely looking at powder/carbon staining. Remnants of the black nitriding, or even shadow. Yes, shadows appear in a pristinely clean bore and some ruin their barrels chasing the shadows. They continue in the fool's errand thinking black patches indicate carbon removal, but in reality it is forever blackening tarnish from polishing metal.

 

[FredHammer]

There's really not enough context or picture quality to tell what you're looking at. But that looks like a shit barrel. Tool marks, divots or cavities. What barrel is this?

Oh great! Now you're gonna get him all fucked up in worry!
Those cavities are caused by rust/barrel pitting.
As far as tool marks...if a bore shooting good, no worries. If a bore shooing bad, that's it!

 

[FredHammer]

I'm not suggesting he do anything about it. I can tell it isn't a quality precision rifle blank. I'm betting it's a shitty AR brand. Looks like a low quality bore.

I'm not suggesting you are suggesting! It was a light hearted joking post with a big corny smiley face!

 

[IDbound]

Thanks for all the responses. It is a Tikka barrel in 6.5 CM that shoots one hole (touching) groups when I do my part. Not worried at all about the other marks. Did notice a little "fire cracking" on one of the lands so I will just take it a little easier when doing new load testing or long range plinking. The only reason for buying the scope was to see if I was developing a carbon ring from not cleaning the run after 100 rounds or so. Everyone has an opinion on that subject of how often to clean so don't want to go down that rabbit hole.

 

[IDbound]

By the way, I am parting on the explanation/belief that it is "carbon staining". That makes the most sense as in other pictures I can still make out the lands.

 

[wind gypsy]

Thanks for all the responses. It is a Tikka barrel in 6.5 CM that shoots one hole (touching) groups when I do my part. Not worried at all about the other marks. Did notice a little "fire cracking" on one of the lands so I will just take it a little easier when doing new load testing or long range plinking. The only reason for buying the scope was to see if I was developing a carbon ring from not cleaning the run after 100 rounds or so. Everyone has an opinion on that subject of how often to clean so don't want to go down that rabbit hole.

You can buy a takeoff 6.5 tikka barrel for $100, i wouldn't trouble yourself with "taking it easy".

 

[IDbound]

Thanks for the suggestion. Any place to look in particular for a takeoff.

 

[wind gypsy]

Thanks for the suggestion. Any place to look in particular for a takeoff.

JA outdoors has them occasionally for in the $150 neighborhood. I've seen a lot of them for sale on forum classifieds, rokslide in particular. They are on Ebay as well.

Lots of people using tikka rifles for donor actions these days and they keep tolerances tight enough that a factory barrel SHOULD headspace on a different action without modification. I took off the factory 6.5 barrel on mine without firing it but for the $100 i'd get out of it I kind of like keeping it around in case in want to screw it on someday.

 

[IDbound]

JA outdoors has them occasionally for in the $150 neighborhood. I've seen a lot of them for sale on forum classifieds, rokslide in particular. They are on Ebay as well.

Lots of people using tikka rifles for donor actions these days and they keep tolerances tight enough that a factory barrel SHOULD headspace on a different action without modification. I took off the factory 6.5 barrel on mine without firing it but for the $100 i'd get out of it I kind of like keeping it around in case in want to screw it on someday.

Thanks!