Certainly no metallurgy phd here but the interior of the barrel looks as though it has inclusions of some sort. If that is the case, and is the downstream cause of your accuracy issue, you’re headed toward a new barrel.
“When Tyranny becomes Law, Rebellion becomes Duty”
Colossians 3:17 (New King James Version)
"And whatever you do in word or deed, do all in the name of the Lord Jesus, giving thanks to God the Father through Him."
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