Most are aware of the .040 inch height difference in the F marked FSB. Colt carbines made before the advent of the M4/F marked base had .040 inch taller front sight posts. Does this really matter when you are using an A2 fixed handle upper receiver? Is it necessary to use the .040 taller front sight post?
Ralph
If you are using a a2 upper receiver the correct front sight is the non-f marked one. No you do not need the taller front sight post. An F marked front sight with the normal post can be zeroed as well.
It depends on whether you'll be using it on a carbine or rifle. A 20" gun won't require an F-marked FSB or the alternative taller front sight post due to the longer sight radius. Chances are, a carbine WILL require an F-marked FSB or a taller front sight post regardless of the type of upper receiver being used (A1, A2, A4/M4).
Originally Posted By F14ADC:
Most are aware of the .040 inch height difference in the F marked FSB. Colt carbines made before the advent of the M4/F marked base had .040 inch taller front sight posts. Does this really matter when you are using an A2 fixed handle upper receiver? Is it necessary to use the .040 taller front sight post?
Ralph
No
Originally Posted By 86HMMWV:
It depends on whether you'll be using it on a carbine or rifle. A 20" gun won't require an F-marked FSB or the alternative taller front sight post due to the longer sight radius. Chances are, a carbine WILL require an F-marked FSB or a taller front sight post regardless of the type of upper receiver being used (A1, A2, A4/M4).
Yes, this does concern the carbine.
Ralph
Seems to me that the more cost effective method would be the taller sight post vice the forging of a new FSB.Doe anyone know why the decision was made to use a taller FSB vice the taller front post?
Ralph
