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Page AR-15 » Build It Yourself
AR Sponsor: bravocompany
Posted: 9/11/2010 1:25:04 PM EDT
I built a 20" upper using a Bushmaster 20" barrel and an LMT flat top upper receiver and am having some trouble sighting it in. I am using a Colt A3 carry handle for the rear sight. When I zero it at 25 yards, the closest I can get it to the point of aim in elevation in about 7"-8" high. The bushmaster FSB is not F marked. Does anyone know what would cause this?
Link Posted: 9/12/2010 7:27:07 AM EDT
[#1]
You need to get the  taller front sight post from bushmaster. Part number 9349056-M
http://www.bushmaster.com/products.asp?cat=21
Link Posted: 9/12/2010 8:11:40 AM EDT
[#2]
Use a sight height correction calculator to determine how much is needed.  You might have to get the front sight post and a different carry handle.  I think Bushmaster carry handles are build at a different height.  Remember, key word here is think, like not sure.

http://brownwells.http.internapcdn.net/brownwells_vitalstream_com/sightCorrection_F2.swf
Link Posted: 9/12/2010 9:31:02 AM EDT
[#3]
Check out KNS pins...they have the .04" taller sights as well as some with points, beads, and notches. Gives you some more options.
Page AR-15 » Build It Yourself
AR Sponsor: bravocompany
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