Charles Daley AR15?

[12Pump]

Besides CMMG, ArmaLite, BCM and PSA midlengths have triangular end caps. Daniel Defense is unusual in that it uses round end caps for midlength. Almost everyone uses round end caps for carbine length gas.

Actually, that shape you refer to as a triangular end cap is actually just part of the handguard itself, rather than a cap. I still have the handguard off the rifle and took a couple pics of it separated, and joined together. Just for the fun of it, I also included a couple pics of the bolt that I just took now that there was some actual sunlight I could use. These pics look better.

 

[Jackal]

Actually, that shape you refer to as a triangular end cap is actually just part of the handguard itself,

We are referring to the triangular steel keeper at the back end of front sight base that the gas tube goes through.

#8 in the pic
http://www.brownells.com/userdocs/schematics/colt-gastubeassembly.gif

Its unusual for a carbine to use the triangle shape and not the round one.

 

[12Pump]

We are referring to the triangular steel keeper at the back end of front sight base that the gas tube goes through.

#8 in the pic
http://www.brownells.com/userdocs/sc...beassembly.gif

Its unusual for a carbine to use the triangle shape and not the round one.

Ah, yes. I see it now. Here's a pic of mine. It does seem odd that I'd have that if it's a complete factory CMMG upper and they originally made it that way. But then again, I'm not familiar.

 

[Quentin]

Yes, that's a good picture of the triangular end cap and the govt profile barrel.