Guys,

I'm looking to fix or trouble shoot a bit of a problem I'm having with an A2 rear sight. The elevation knob will not rotate much past the 4 mark. Then, it stops cold.

This iisn't my "go to" rifle, so I don't mind tearing it down for a while.

Have you guys disassembled any A2 rear sights? That, and a barrel swap are the only things I haven't done yet.

Is it a horror show? Impossible to reassemble? Lots of swearing and blood?

Please advise.

Brownells has a video.  http://www.brownells.com/.aspx/lid=11435/learn/
You do not have to have all the tools it say but it shows you how to do it.
Sometimes the ball bearing likes to take roll somewhere. Also pushing the spring in and driving the roll pin past it through the upper takes a little work.


Also the TM manual from the ar15 home page library shows how to do it.

I just assembled one a few weeks ago and it was a major pain in the ass.

Getting the elevation knob spring roll pin in, even with the tool that Brownell's sells, can be a pain in the ass.

The Brownell's video makes it look pretty easy and perhaps if you've done it a few times it is. I just didn't think so.

Regarding the issue you're having, there is a small hex-head screw that is used to hold the top ring of the elevation knob to the bottom ring of the elevation knob. If the screw has backed out a bit then you could definitely have issues turning the elevation knob. There is a hole in the top of the rear sight that allows you to access this screw.

Thanks guys.

It has been a while for me.  I would suggest having a very clean work area.  INCLUDING FLOOR!!!!!!!!!  No really those damn bearings roll where ever the hell they want!  If I had to I would do it again.  But I sure don't want to!!!!

I have only done it once and I didn't think it was all that hard.  But I did drop one of the ball bearings.  Dang thing cost me around $4 after it was shipped.  That was the only pain.  Then I found the one I dropped a few days later after I installed the new one.  

The best thing to do is just give it a whirl.

Work over one of those magnetic trays, it's damn near black magic.

good idea ––there are small springs and a small ball bearing easy to loose ––make sure you follow the tm and remember how it is supposed to be.

Put a thick grease, axle grease, fancy lube grease, whatever on the spring end, spring hole, and ball bearing.  It then tends to sit there held by the grease awaiting spring compression.