For people who think the AR is not a piston driven rifle. It is not DI

[montana]

I thought most people, "who own AR rifles" new it is a piston driven rifle and not direct impingement. I have used the term DI myself, but it is an "internal or in line Piston, not DI. MAC explains it pretty good, but he was incorrect when calling the bolt the piston. The bolt carrier is the piston,"not the bolt" and works like any other gas cylinder cup piston but is internal or inline.https://www.youtube.com/watch?v=ZYuuFSxcDTs

[depletedyourcranium]

MAC is correct but he's being totally pedantic here. It's not like theres a bunch of other contemporary DI guns that we need to distinguish the AR15 from. It's less important what people call it than it is that people truly understand what is happening within the action itself.

Nonetheless the video does a great job of explaining what exactly makes the AR a great action. Piston kits and piston-AR derivatives are one of my pet peeves. They create more problems than they solve (which is usually none).

[bj139]

Doesn't a piston gun control the piston through it's length of travel? The AR-15 does not. Maybe that is why it is DI.

[montana]

MAC is correct but he's being totally pedantic here. It's not like theres a bunch of other contemporary DI guns that we need to distinguish the AR15 from. It's less important what people call it than it is that people truly understand what is happening within the action itself.

Nonetheless the video does a great job of explaining what exactly makes the AR a great action. Piston kits and piston-AR derivatives are one of my pet peeves. They create more problems than they solve (which is usually none).

External piston AR's have their place, as the HK416 has proven. I don't agree with the no lube. Yes, "carbon will gum up with certain lubes over time" like grease, but when the AR becomes over gummed up with carbon and oil, it will keep running if kept properly lubed. The few drops of oil here or there is ridiculous as far as my experience has shown. If a bolt is over lubed, it will blow out the excess and burn off over time. Better over lubed than under. For military applications where dirt becomes a factor it maybe true but not in my world.