I’m running a non-chrome lined with a Opsrey Defense 416 piston kit, 14.5 barrel (with pinned&welded flash suppressor to 16.33 inches). The fact that the chamber stays cool enough to grasp even after a couple hundred straight through it may have a lot to do with the ‘fouling chamber’ effect not showing up. DI guns dump a lot of carbon into the bolt which finds its way onto the walls of the firing chamber as the gun heats up. I run three different guns, one a 10.5 inch pistol version, all have a different piston system on them (CMMG on the shorty, Osprey on the 14.5, and Adams Arms on a 16 inch carbon fiber with chrome lined bore). I almost feel guilty for not cleaning them every time I shuffle out to the range for a few hundred rounds. ... But you get used to it, trust me.
That’s awesome. Seems like the piston might be making a difference in how much “stuff” ends up in the chamber, especially when firing steel cased ammo.
Good to know.