Hearsay out on the street was that they are AR barrels, thus the gas port is oversized to be utilized in a piston gun.
I think it was the Dlask barrels that were just AR barrels with a cut for the op rod guide. They are severely overgassed to the point it causes failures. The simple "fix" is to run it with the regulator in the S (suppressed) position to reduce the amount of gas making it to the piston.
I am not 100% sure it was the Dlask barrels though, there were a few guys trying to supply barrels to the guys who couldn't afford the Herron Arms treatment but some of them did not do any research and didn't realize that just because it fits the rifle it wasn't built for the gas system.
Arms East barrels are supposed to be good, I know a couple guys that bought them and they were accurate and reliable.
I've owned 2 ACR's and currently own one NR stainless barrel sold by Questar in 223 with a Wylde chamber that runs great, I also have a NR stainless 300 Blackout barrel I built for it that runs great.
I had a 6.8SPCII stainless barrel for it which I sold after I got it cycling but the guy I sold it to had issues with it in his rifle, not really sure why that happened but it was a weird one.
Not sure of your rifles current status but just remember that if it's restricted installing a non restricted barrel does not instantly allow you to take it out to the bush. It needs to be inspected by a certified firearms verifier and then you need to wait for the CFO to take it off the books before it is actually a non restricted rifle.
And don't let the wishful thinkers convince you that there is a 30 day grace period where you can switch it back and forth and do whatever you want. I spoke to the CFO when I was converting mine and they said if the rifle is currently registered as restricted the 30 day period is for you to take it to the verifier and get the paperwork done. Until the CFO actually removes it from the registry it is still classified as restricted and can only be used at a range.
