What is Mil Spec the "F" FSB are the Standard FSB?
If you have an A2 style rifle you would want the standard FSB, if you have an A3 or railed upper you want the F marked FSB. F denoted flattop rifle. They would both be MilSpec if they meet the requirements of "MilSpec"
Thanks for the great info StlBluesFan. You answered a question I had.
Is the height difference between the standard FSB and the F FSB the reason the flat top adjustable rear sights are marked 6/3 and the fixed handle A2 adjustable rear sights are marked 8/3?
Sights in the fixes A2 handle are adjustable out to 800 meters hence the 8/3 adjustments. The screw would be too long for a detachable carry handle, and would stick out of the bottom, so they are only adjustable out to 600 meters. There are some cheaper carry handles I have seen that have the 8/3 elevation ring, but I think they just chose to stock only one part.
FSB
Linear Mode
