Parts AR shooting way off to the side

[FLcracker]

Maybe. Check the red dot and make sure it is grabbing and tightening correctly. Sometimes they van get wonky??

If the red dot feels like it is mounted correctly, move on to the next item. Got any iron sights?

I had started to suggest that if it was a cheap red dot, it was probably the red dot. I have that happen before. But the Sig should be GTG.

 

[GAgunLAWbooklet]

Instead of dealing with this problem, sell it to somebody at Atlanta Antifa.
Tell them it only shoots people ON THE RIGHT !!

 

[Jambo]

Move the red dot forward until it can get a "bite" on the entire upper.

Push the red dot forward as you tighten it, since it will want to move forward under recoil.

Check that you don't have a screw or something inside the forearm or freefloat tube pressing on the barrel. I recently had a friend with home build and one of his sling mount screws was pressing against the gas block.

 

[Plinker66]

Thanks gentlemen. The other day I moved the red dot up a couple of inches and that helped some with the dot moving with my eye position. I also loosened the six ALG freefloat mounting screws, and then beat on the freefloat with a leather hammer, and then tightened the six screws back up while applying some pressure to take up any slop in the mounting screw holes. That helped a bit too. It’s still off to the side too much for my liking but I believe the deviation is in the tolerances within the upper Receiver or the freefloat rail and it shoots good nuff for the red dot so I’m gonna leave it for now.

 

[opps]

Looks like the rail billet was not centered in the mill properly.

 

[1006]

Are you sure that the free float hand guard is straight?

 

[Plinker66]

No but the free float and the barrel are lining up together much better than the free float and the red dot.

 

[Mr. Booshie]

Ive got a laser bore sight of you want to use it.

 

[Necrosis]

Red dot should be as far forward on the receiver picatinny rail as you can get it, it helps to reduce parallax shift from inconsistencies in head placement. Sight the red dot in, line the iron sights up with it to get a rough zero on them and then fine tune the irons from there. If you can't get the irons close because of the rail twist, move them back onto the front and rear of the receiver rail or ditch them entirely.

 

[FreedomUSMC]

Try a different optic (or irons) on the rifle and test, that'll determine if it's the rifle or your optic.