I'm putting a Fulton Armory unitized gas cylinder on my M1A. It's a Springfield Loaded model, and according to the SN it was made in 2009. It has a Springfield barrel and mostly Springfield parts. A while back, I ordered a NM flash suppressor with a bayonet lug, ordered it from Brownell's I think. I put it on and haven't thought about it since. Today, I took it off to put the gas cylinder on, and I saw something in the flash suppressor keyways. I though it was crud or maybe some 4895 powder that made it's way in there so I went to push it out with an allen wrench. I saw that there were spots where the finish was rubbed off under them which make me think they're steel. They look like little pins. If they weren't in each of the keyways, I would think they just got in there, but this makes me think they were put there because they are perpendicular to the keyways and they all fit good. are they some kind of shims to keep the flash suppressor on straight or are they junk that worked its way in there?