On a related note and not to hijack your thread, I’ve been looking at piston driven AR-15’s for the past week. I keep hearing how much cleaner running they are than direct impingement AR’s.
That’s good to know, I’m gonna have to look into that and see it myself to see how clean it is.
Piston ARs were a fad a few years ago. Enthusiasts often bought aftermarket drop-in kits to convert their direct impingement (DI) rifle to piston operation with varying results of reliability. They also learned that piston-operated ARs designed and built as a single unit by even reputable manufacturers didn't offer suitable reliability.
The entire point of the piston-operated AR was to improve reliability over a DI rifle by reducing gas-operated fouling, and too many users found that a freshly clean piston AR ran worse than even a standard DI-operated rifle that had heavy powder residue fouling inside the action.
I recommend keeping your AR standard DI spec. If you must have a piston-operated rifle, you should choose a rifle that was designed that way from the beginning.
Actually, I’ve heard that a whole lot of operators stopped using piston ARs a few years ago and switched back to DI rifles. A well built DI AR-15 will work long and hard before needing cleaning, I’ve read that a Bravo Company bolt and carrier group can go thousands rounds before cleaning.