I think I've read that rear sights attached to flattop uppers tend to have zeroing problems.  I assume the problem would be more so using the DPMS lo-pro which states that its upper is slightly higher than normal.  

Which rear sight would line up best with a standard Bushmaster FSB on a Bushy 16in heavy barrel?

thanx

I've got the A.R.M.S. #40L and I love it.  Zero is not a problem and it stays out of sight if you want it to.  I like it more than the standard #40.

Troy industries rear BUIS and a .040 taller front sight pin from brownells.

I prefer the Troy over the ARMS for two reasons. First, when you flip the Troy open, the big aperature is in use first. My thinking goes like this, if your optic fails and you need a BUIS in a hurry, you'll need the large aperature. If your optic fails and the target is a long ways off, you'll have time to switch to the small aperature. The ARMS is spring activated and requires only a flick to open, BUT there is nothing holding it open except the spring. With a Troy, you push it open, but it locks so solidly there isn't any wiggle at all. The Troy is still really easy to open anyway.

You need the .040 taller sight pin because bushy barrels don't use F marked front sight bases.

thanx - I should add that I plan to use a kns precision sight in the fsb.  How does that affect the height differential?  Is there a particular brand carry handle type that would best align the sights?  Aren't some handles squater than others.  I guess it's a sign of playing too many video games, but I prefer to have a crosshair.


edit - I was going to use DPMS southpaw lo-pro upper because I thought it was slick on both sides.  Turns out that even though it ejects on the left, the right side still has the case deflector.  Kind of silly.  So now I'm back to thinking I'll get the Stag lefty upper.  According to the boards here it's (Stag) supposed to be much better quality.  hinking.gif

i have a YHM on both ends there cheap and rugged