Not going to argue. I just have had a couple of chances to run ARs really heavy that have had NP3 on the BCG, and totally dry they will run over 1500s rounds before they choke. With standard parts a dry AR/M16 wouldn't go 100 rounds in my experience.
Now you have me worried I'll be growing a third eye from breathing Teflon fumes from those guns.
Personally, I'd go with a silver BCG if I had a choice, gives a better visual on lube, carbon build up, etc.
Bill.
How new/ recent manufacture is the M&P you are working on?
Are you seeing any indications of the warped slides or eccentric barrels previously noted in some of the 9mm M&Ps?
I have no idea how old this gun is. This one, though it's a 40, is straight as an arrow. I wouldn't be spending the time/effort on it, much less sending it back to someone who might actually need it in the line of duty if I didn't check it out thoroughly.
Though, the crown and bore finish is typical S&W. I'm sure Tam can describe that more colorfully than I.
While doing Glock internals, can you coat the trigger bar?