I have an ARMS 40 on a rock river A3 style, and to get the sights correct, the BUIS heeds to be adjusted almost all the way to the right.  Is this normal?  If not, what can I do to fix it?  Thanks.

either make sure the arms is mounted on there correctly/flat or eyeball the fsb to see if its is canted.


if the fsb is canted whack it with a rubber mallet in the direction it needs to go.

Not normal.  Look at the locking bar on the left side of the sight.  Is the little arrow pointing toward the front of the rifle?  If it's upside down (arrow pointing towards the butt of the rifle) it could cause some wacky fit issues.

whoa-
Not trying to be a smartass but what will whacking the FSB with a rubber mallet do?  On mine, I can't see how the FSB could move.  The FSB pins through the barrel and fit of the barrel extension/indexing pin into the upper probably won't allow any movement.
Thanks