Noobie here.  After using multiple AR forum sites decided this was the best one.

I had an OEM hand guard, two piece on a RRA Delta carbine.   I have EOTECH XPS2 and MBUIS sights.   I was wondering why the rear aperture was so far to one side.

Turns out the OEM handguard rail was not level with receiver rail.  Plus it had some rotational movement.

One of the reasons I got a one piece  hand guard I was expecting the rails to be more level.  Well it turns out its not level (or close) either.

 (I hope the pic link works!)

I used the gas tube alignment rod to install base for rail.  And torqued to spec.  Gas tube itself slid in with no resistance.  By this design I really expected the rails to be closer to level.

I would need to back off nut a hair to make it more level.

Any advice on what to do?  Or am I chasing a problem needlessly?  Just deal with the aperture being way left?  

Thanks in advance,

Mark

Personally, I would level the HG to line up with the upper receiver.  My guess is that it shifted slightly when you tightened it down initially.

That's what I was thinking.    Just wanted to get some advice before I redo the setup.

If I back off the nut might not be torqued to spec, problem with this?

It depends on how much you have to back it off.  Torque spec is a pretty broad range, so you do have some room to play with.  If you really want to be anal about it, you could shim the receiver.

the anal one got it all lined up.   Backed it off about a hair".

After attaching the handguard  noted that the barrel was not in the center of the handguard, not good.

So I torqued the six screws like nuts on a tire.  Still off center.

Then used a McGyver trick, had two plastic wedges inserted between handguard and barrel. Made sure barrel is centered,  Then tightened the screws.

Perfect now

Making sure everything is centered gets way more involved after you get a lathe.