hairline rings inside barrel on inspection - problem?

[Phildo]

Gday team, would you mind commenting if you're familiar with this condition?
I'm an amateur, just wondering what might be happening with this stock Howa barrel.



Video of inspection here:
https://www.youtube.com/watch?v=FJG8S2uoA7E

[Malcolm Hill]

Hi. I had a look at the video and that barrel certainly has been very neglected in the cleaning department. There is an abundance of copper fouling as well as carbon underneath and it looks like a fair bit of rust pitting as well. Give it a good clean with Hoppes, Sweets and carbon cleaner to get the fouling out to be able to get a good look at the rings around the barrel. I doubt they are cracks as they are all so uniform in depth and direction. Not usual for cracks like that in a barrel. More likely they are marks left from the reamer prior to the rifling process. Best get the barrel clean and have another look and get someone else more experienced with barrels or a gunsmith to check it out. Regards Malcolm.