I guess I wasn't quite as offended by the "front" gas block on my camo 20"...BM puts 'em there on several different models, as a mount block for their "V-Match" sight system (whatever that is)...I used it to mount their V-Match flip-up front BUIS, and put a flip-up rear on the receiver rail. Works for me. I did mod the front post, changed it to a KNS hooded duplex crosshair...much easier for old far...oops, I mean old timer eyes.
(another zombie thread...risen from the dead...
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