Mounting Optics and F-BUIS on Railed HG?

AR/M4 AR General Discussion
1

Both of my AR’s are running with LaRue free floating rail systems with the front BUIS on the rail over a LT lo-profile gas block. However, on one of my AR’s, I run an Eotech 512 out on the HG, on the rearmost notch of the HG. (FYI, the other AR has an Aimpoint in an LT mount on the last receiver notch.)

Is there any downside, particularly loss of zero in the optic or BUIS if they are mounted in this manner? I see a lot of guys running BUIS on FF rails, but hardly any with optics in this position. I love my 512 in this spot; 65 MOA ring + huge eye relief = great shooting, although it messes up the balance a good bit.

So any of you FF rail guys getting any issues with these setups? I do see that M4C is mostly a fixed FSB lot. :smiley:

2

So no one at all has tried this? Does anyone have any horror stories to tell?

3

i’ve seen this done on a lot of conventional guys’ rifles. from what i gather some say it’s faster for reflex shooting. personally i feal that the hand guards are the most unstable place to mount optics due to the fact that they’re made to be taken on and off. maybe with a monolithic rail the case might be different but i dunno. i tried it once just for shits and giggles but didn’t like it mainly because it’s just so different for me. i’m just used to my optics being on the receiver. also it adds more weight to the front end of your rifle…and it looks stupid. just my thoughts.