Gas Tube Issue

[BMXnotFIX]

I'm sure this has between asked before but I couldn't find any answers for the life of me. I am almost finished building an AR15 with a 20" hbar barrel. The barrel is rifle length but the gas tube seems to not be hitting the gas key on the bolt correctly? When the bolt is in battery it pushes the gas tube and block forward about half an inch. I bought two of the same bolt and the other one is in a pistol build and seats fine. Not sure what's wrong. Stupid fix?

[nate76239]

Where did you get the gas tube? I think Armalite .308 has a slightly longer gas tube than an AR15 or DPMS 308. Also I think once somebody incorrectly installed the gas tube roll pin in front of the tube

[BMXnotFIX]

Nothing is staked yet, all loose. Do you by chance know the length of a standard 5.56/.223 rifle length tube? I got it off another CGer so that's a very possible reason.

[nate76239]

I can't tell for sure because it's already installed on the rifle but looks to be about 15 inches from the roll pin hole to the end of the tube

[BMXnotFIX]

I'll see if I can find specs.