I've never removed the gas rings from my bolt, but I've begun to question the identity of mine:  if I can see three distinct rings, and I can see the gaps, then can I safely assume that I've got the "standard" gas rings and not the McFarland Gas Ring?  
This question is related to another thread that asked about the value of the McFarland setup, and the statement by one of the most beloved and respected moderators that Armalites have the McFarland setup.  I have one that doesn't, and I'd like to know if this should be a concern.

No need to run to the safe to pull the gun and pins and bolt out just to check, but I'd like to know if I've got the original Armalite factory bolt.

[I just read a recent post on the first gas ring thread that made me think that I may have McFarland rings, but not a one-piece ring.  Are all McFarland rings one piece?)

Thanks.
(Guess that it was a longer question, but it still ought to have a quick answer)

Unless they changed them, McFarlands are one single piece. I tried one for a while but it was a bit too tight inside a chromed bolt carrier. They were cheap, like 80 cents each. I've been using the stock 3 ring setups for a while with no problems. I kept the McFarlands as spares.

Well, I guess that I can assume that the bolt, or the rings were swapped sometime before I purchased the rifle.  Incidentally, I bought the rifle NIB. . .
Is there any other Armalite owner who bought an M15A2 with the standard (non-McFarland) setup?

Quoted: Well, I guess that I can assume that the bolt, or the rings were swapped sometime before I purchased the rifle.  Incidentally, I bought the rifle NIB. . .

Maybe that was before Armalite switched over the newer type rings. I've personally never had a problem with the GI style rings as long as you keep the gaps staggered, like piston rings in your car.

Most people don't even pay attention to how the gas rings are positioned. Fact is, they can and do move around while the bolt is in motion, so staggering them is pointless. The internal engine piston ring is not relevant as the pistons have pins in the ring grooves to prevent the rings from rotating and possibly having the gaps line up.

If your weapon is having problems that staggering the gas rings seems to alleviate, the true source of your problem lies somewhere else. Staggering the gas rings is only a band-aid fix.