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5/29/2015 7:23:12 PM EDT
I just noticed that the front sight post on one of my new uppers is loose.  It rocks back and forth in the FSB about an 1/8" in either direction.  Is this going to cause any issues with sighting in / maintaining a consistent POI if the post moves slightly with each shot? Thanks.
5/29/2015 7:24:29 PM EDT
[#1]
Photos would help. Is the FSB pinned in with taper pins or screwed on?
5/29/2015 7:28:26 PM EDT
[#2]
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Quoted:
Photos would help. Is the FSB pinned in with taper pins or screwed on?
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I'll try to post some pics later.  The FSB is pinned.  The FSB is solid, it's only the post that's a little loose.
5/29/2015 7:37:20 PM EDT
[#3]
Is there a spring under the post?
5/29/2015 9:58:12 PM EDT
[#4]
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Quoted:
Is there a spring under the post?
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I'm pretty sure there's a spring under the post.
6/2/2015 3:38:56 AM EDT
[#5]
1/8" is a lot of slop! But you can run an 8-36 tap through the front sight to clean up the threaded hole and then install a short stainless set screw from the bottom. Just snug it up when you get the elevation where you want it. Put a drop of light oil in there occasionally and you'll not have any problems. I've done this on several rifles. It doesn't alter anything and you can remove it at will.
6/2/2015 4:12:27 AM EDT
[#6]
Quoted:
I just noticed that the front sight post on one of my new uppers is loose.  It rocks back and forth in the FSB about an 1/8" in either direction.  Is this going to cause any issues with sighting in / maintaining a consistent POI if the post moves slightly with each shot? Thanks.
View Quote


How high do you have the sight raised? Are you using a non F-marked FSB with a standard height post?
6/2/2015 7:27:19 AM EDT
[#7]
Quote History
How high do you have the sight raised? Are you using a non F-marked FSB with a standard height post?
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This is what I thought as well, never seen any sight post with that much play, which will absolutely ruin any degree of accuracy.

If you don't have a standard height FSB taller posts are available. I'd determine which height sight post you need and replace it before you do anything to the base. Posting a pic here will get you the fastest answer.

When you adjust your sight post, do you have to push down the spring detent pin in front of the post to get it to rotate?
6/2/2015 7:40:35 AM EDT
[#8]
Topic Moved
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