Rifling Condition Question

[Willyw]

Hi all,
New shooter and bought my first bolt action rifle used online. Rifle came in and I tried to zero it at 100m. Couldn’t hold zero if my life depended on it. During cleaning I saw what looks like a ridge near the muzzle about 4” down. Is this the cause of my accuracy problems? What could cause damage like that or is it nothing to be concerned about? The rifle has a small muzzle brake installed by a gunsmith with the previous owner

My groups have been improving so I’m not sure if I’m just a novice or the barrel is still breaking in. I hope it’s not time for a barrel replacement already

https://www.dropbox.com/s/ryf47oxsp8cicf7/Photo%202021-09-16%2C%2012%2006%2057%20AM.jpg?dl=0

[fire@will]

Can't really make much out in the picture, but if there is a ridge in the bore/barrel, that could very likely cause accuracy/inconsistancy issues. The bore should be perfectly straight, smooth and clean, throughout. You might have a gunsmith take a look at it, for a professional opinion.