I did some measuring today of my A3 rear sight assembly and made an interesting discovery. The rear sight indexing marks at the sight base are off center of the inside diameter of the base by .5mm (inside diameter is 15mm., center mark should be 7.5mm. from either inside edge, center mark is 8mm from the left inside edge, 7mm from the right inside edge). When zeroing my weapon at 25 meters, I had to come left 8 clicks, which is approximately .58mm or 1 notch of the sight base markings! I believe, therefore, that my indexing problem is actually a sight base index marking innacuracy and possibly not a barrel torquing problem. Any ideas on this? Bushmaster, have you come across such a sight base indexing problem? I recently purchased (August, 2002) my A3 Dissipator; would I have to send back my entire upper to resolve this problem? Many thanks in advance.
edited for "dummyhead" grammatical errors