Gas Tube Alignment Tips

[Heavy Metal]

Please post your tips for acheving the perfect, no-drag gas tube alignment.

[C4IGrant]

Please post your tips for acheving the perfect, no-drag gas tube alignment.

I have a metal tube that is the same diameter as a gas tube. I use this to initiall get the barrel nut lined up with the gas tube hole in the receiver.

I then take the gas tube and insert into the receiver so that it will line up with the gas port on the barrel. I look for any binding in the receiver hole and see if the opening in the gas tube is DIRECTLY centered over the gas port hole on the barrel.


C4

[Robb Jensen]

I use the good old Mk1 eyeball and a gas tube alignment tool.

[mvician]

I forget the size offhand but I use a drill bit and run it thru into the gaskey.

[spr1]

Most of the above followed by a final check using a tool to guage that the tube is centered inside the upper receiver left to right.

[seb5]

Added to the above. After finding the correct spoke and checking torque to make final minute adjustments I will sometimes use a long cheater bar for extra leverage to avoid having to back off and start over.

[Heavy Metal]

I can get the left-right thing pretty well. I have the end of an lod tube I use for a guage. It is the up-down adjustments I really want insight on.

[seb5]

Up and down?...........Well I have seen people take a flat round object like a pencil/eraser to push it down slightly for small adjustments but I've never done it, never had to. I think if it's not fitting there might be other problems.

[OldNavyGuy]

i have a stainless steel rod about 16" long, (i do not recall where i got it from) that fits quite snugly in the gas tube hole (clover leaf) when i get all the holes in the delta ring assy., barrel nut and receiver closely eyeballed, i insert the S.S. rod then continue to torque the barrel nut till the rod is perfectly lined up with FSB, i remove the rod and insert a discarded gas tube that was installed improperly by a former owner of an AR-15 i bought, if it slides fore & aft easily i consider it lined up, then i darken the end of the tube with machinists ink and rack the action several times and check the end of the tube for contact with the gas key, the results is the ink is evenly removed by the action, i then consider the job done.

sounds complicated, but for me it is easy as i have used this method for years and never had an alignment problem.