Here's the full story.
My friend (yes an actual other person besides myself who's older, fatter and richer than me) wanted a 224 Valkyrie AR15. He's a bolt gun guy who previously had zero interest in AR's. I recommended he buy a factory rifle but he insisted we put it together ourselves. He wanted a top of the line barrel so he contacted craddock precision who spun him up a bartlein 224 barrel. We put that rifle together, shot it out to 900+ yards and he's very pleased with it.
He then wants another precision AR. I point out he can just get another upper and save some money. He decides on the 6ARC caliber. He contacts craddock who is now on a 6 month lead time (only took 2 months for the 224 barrel). He doesn't want to wait so he looks around and finds precisionfirearms.com. They have a 6ARC medium weight 22" fluted barrel already threaded 5/8-24 in stock so he buys it.
He gets the barrel and we immediately notice the thread issue I've discussed here. We take the barrel to a local guy who is extremely knowledgable about precision rifles and specifically bartlein barrels. He's literally bore scoped 50+ bartlein barrels in both bolt and semi-auto rifles. He has built precision rifles and teaches long range shooting and and manages a stable of precision rifles. He bore scoped the barrel for us on the stop. The chamber was "perfect" the finish on the inside of the barrel was outstanding, the gas port was perfectly centered in a groove. Besides the shit-ass threading job the barrel should be a shooter. My buddy decides that he wants to shoot the gun and see how it groups. If it groups well he decided he would send to it a professional shop and get the barrel re-threaded.
We shot it, it shot well, you know the rest of the story.