Sight base ? > AR Discussions

Posted: 3/15/2012 11:41:14 AM EDT

I did a search and checked the FAQ but couldn't find a answer.

I have a A1 carry handle upper and I want to pair it with a 14.5" carbine barrel with a F marked front sight base. Will this be a problem? My understanding is that the F marked base is taller. Can the front sight post be screwed down enough to compensate?

Posted: 3/15/2012 12:24:58 PM EDT

[#1]

Quoted:
I did a search and checked the FAQ but couldn't find a answer.

I have a A1 carry handle upper and I want to pair it with a 14.5" carbine barrel with a F marked front sight base. Will this be a problem? My understanding is that the F marked base is taller. Can the front sight post be screwed down enough to compensate?

You need a standard height FSB.
The F marked FSB is for flat top receivers and is .040" higher than what you need.

Posted: 3/15/2012 12:35:51 PM EDT

[#2]

Most of the time it will work. You'll just need to screw down the sight a bit more.

Now I said 'most of the time' there are times when the manufacting tolorances won't stack in your favor - but it's impossible to know till you try.

Posted: 4/25/2012 5:17:48 AM EDT

[#3]

Quoted:

Quoted:
I did a search and checked the FAQ but couldn't find a answer.

I have a A1 carry handle upper and I want to pair it with a 14.5" carbine barrel with a F marked front sight base. Will this be a problem? My understanding is that the F marked base is taller. Can the front sight post be screwed down enough to compensate?

You need a standard height FSB.
The F marked FSB is for flat top receivers and is .040" higher than what you need.

IF you have .040 height issues the real world expedient is to simply remove the sight post from the FSB and gently file .040 off the top. It is NOT a big thing !

Posted: 4/25/2012 5:32:15 AM EDT

[#4]

You should be fine, just screw the front post down 5-6 clicks

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[ARCHIVED THREAD] - Sight base ?

[ARCHIVED THREAD] - Sight base ?