I’m not having trouble, I was just wondering how the company’s handeled l it. Your plan seems like a good one.I would shoot few groups with match rounds and email those to them, asking what is the problem. Add a picture of your groups with another gun to show them you can shoot.
Sounds like you spent enough on ammo to buy a barrel.I delt with this with a barrel manufacturer a buddy AR-10. Could not get a rifle to shoot at all. Sent the barrel in once they looked it over and sent back tried again. I probably wasted 300 rounds with mutiple load and powder to no success. Bought several match grade boxes of ammo and still a no go. Sent the barrel back, with photos of all groups and photos of my rifles groups and all items i addressed to be sure their was no other influence causing the accuracy issue. They took the barrel back and sent him a new one and that one is a shooter.