04-10-2023, 02:41 AM
lazyengineer Wrote:Picture #2 compared to Pictures #1 and #3, are the tell that it's an uneven concentricity. This is WAY more common than people think. The reality in my own experience is there are two places that matter in a barrel, the throat, and the crown. In between basically doesn't hardly matter at all. It's why a pitted and corroded barrel, or a barrel damaged by fugitive steel media, can still shoot lights-out. So long as the throat is well uniform, and the crown is good; that barrel will still shoot.
And that barrel - is not.
You have to be careful with optical illusions and dirty aspects misleading you to think mis-machined. So run a few dry patches and reimage, just to be sure. But from what I'm seeing, that is not a square and concentric chamber. Meaning every single shot is starting its journey crooked, within the first 1/2" of its travels.
Cleaned the barrel earlier, took some more photos of the throat area capturing each land (starting with the gouged one).
[ATTACH=CONFIG]19646[/ATTACH]
[ATTACH=CONFIG]19647[/ATTACH]
[ATTACH=CONFIG]19648[/ATTACH]
[ATTACH=CONFIG]19649[/ATTACH]
[ATTACH=CONFIG]19650[/ATTACH]
[ATTACH=CONFIG]19651[/ATTACH]
Here are some photos showing the average finish of the bore including the gas port:
[ATTACH=CONFIG]19652[/ATTACH]
[ATTACH=CONFIG]19653[/ATTACH]
[ATTACH=CONFIG]19654[/ATTACH]
[ATTACH=CONFIG]19655[/ATTACH]
Its really hard to tell looking down the bore from the chamber end, the throat area appears the same to the naked eye.