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9/22/2017 12:11:25 AM
Posted: 1/19/2006 5:32:37 AM EDT
I'm still learning, so please forgive me if this is a dumb question. I have a regular A2 carry handle type upper receiver. I’m interested in buying an M4 style barrel assembly. The barrel assembly has a front sight base that is “F” marked. I’m told this indicates that it is for use with a flat top upper receiver. Will the iron sights work correctly if I mount this barrel to my A2 upper receiver?
Link Posted: 1/19/2006 8:06:54 PM EDT
Does that lack of an answer to my quesition indicate that this is a really dumb question or that it is complicated?
Link Posted: 1/20/2006 5:15:17 AM EDT
My understanding is the F marked front sight base is, its approx. .040 taller than standard fsb for use with removable carry handle on the flat top upper.
On doing a battle zero you will end up with your front sight post screwed down further or possibly bottomed out. I have never done this so I can't say for sure. I'm sure it will vary gun to gun.
For the opposite problem, a std fsb and a flat top, Bushmaster makes a 0.040 taller fs POST.
IN your case IF NEED BE you could remove material from the top of your sight post or just dial up the rear sight , however your numbers on your rear sight would not be calibrated for a proper battle zero just using the rear sight to compensate. No big deal to alot of shooters as they just set em and forget em anyway because they can't or don't shoot over the distances the battle zero is for. UP to 600 if rememberer is working.
The only real way to know is screw it together and shoot it, it might not need anything.
You will be fine either way. Hope I explained it so it is understandable.
Link Posted: 1/20/2006 10:43:56 AM EDT
Thanks Triggerbender. That explained it very clearly. I'm going to give it a try.
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