Hey guys,

So I bought a used factory DD Mk18 upper from here a while ago. I should have inspected it closer then but I'm only noticing now that the rail and upper receiver rail aren't perfectly level. The rail is ever so slightly canted to the left. I noticed this when I was looking through my BUIS through my Eotech. I saw that the left ear of the front sight was lower than the right ear of the sight.

I feel like it's too late to say anything to the seller.. is this purely a cosmetic thing?

I haven't shot this thing yet since I was waiting for a trigger from Larue.

It doesn't bother me too much.. I am just worried that perhaps the accuracy will be effected?

Could I just unscrew the hex screws, straighten it, then retighten?

Thanks

I have one that was slightly canted and I just loosened it up and reinstalled it to correct it.

I placed both the RISll/upper recv. rail upside down on a flat surface, so they were even and followed these instructions for reassembly:

-Place the RIS II™ over the barrel and mate it with the Bolt-Up™ plate. Insert two screws from the
muzzle end through the rail into the bottom two holes in the Bolt-Up™ plate and hand tighten.

-Insert the four remaining screws from the breach end of the rifle through the Bolt-Up™ plate
into the RIS II™ and tighten all six screws to 29-32 in/lbs. using the supplied allen wrench in the
following pattern: the center screws first, the bottom screws next, and the top screws last.

Hope it works for you.

Thanks for the directions!

Does daniel defense apply any thread locker on the hex screws?

Did you apply something like vibratite to the screws?

I'm wondering if I can just try and zero it first..

Yes.  My DD rail had tan colored thread locker on the screws.  If the rail screws don't have that LocTite blue is a good choice. Just a tiny amount on tbe tip of a toothpick is all that is needed.