Ar-15 hanguard quad rail question

[matiki]

I once was issued an M-16 that had a similar problem. Check inside the upper receiver to ensure the bolt carrier key is properly lining up with the gas tube. You might do this by separating the upper, remove the bolt from the carrier, and manually slide the carrier forward until it meets the tube. If it binds, discontinue use until repaired.

In my case, it was not and it ended up damaging the tube and the carrier key (although the rifle still functioned)

That's a good point, I take back my cavalier attitude towards the issue. If the gas tube didn't get bent during the install, then it won't be properly aligned in the receiver... and would potentially cause issues with the bolt carrier key.

[DefensiveCarry.com]

[swatpup102]

Would aligning that barrel nut back up put it back into alignment or no? If it is off when i look at it, would I need a new gas tube?

[matiki]

Would aligning that barrel nut back up put it back into alignment or no? If it is off when i look at it, would I need a new gas tube?

First get the barrel nut properly installed. Then see if the gas tube fits correctly. If it doesn't fit properly, try a new one. They're $12~15 around here. YMMV.

[swatpup102]

First get the barrel nut properly installed. Then see if the gas tube fits correctly. If it doesn't fit properly, try a new one. They're $12~15 around here. YMMV.

Sounds good, I will check this all out when I get home today. Hopefully it just needs a little tappity tap and all is well in the world!

[SubNine]

I put the UTG rails on my M&P15 , they're rock solid IMO.

[Lealbert]

I am replacing the original hand guard on my son-in-law's AR15 carbine with a quad rail. I pulled the hand guards and measured the length. They measure 6.125 inches on the outer body and on the inside when including the mounting rings the length is 6.75 inches. I purchased the Midwest Industries Gen 1 drop-in hand guard (item # MCTAR17). The MI web-site shows the length at 6.125 inches. Does anyone know if this is the right hand guard?

Thanks,
Larry in Katy, TX