Having some elevation trouble with Troy backup sight on AR-15.

[dodging230grainers]

Shot my Colt 6920 at 50 yards today, trying it with a Troy Industries rear backup sight after taking off the carrying handle to simulate my setup with a flattop mounted aimpoint.

Almost ALL my shots were about 3 inches high. As far as I can tell, there's no way to adjust for elevation using the rear Troy backup sight, so my only option is to adjust the front post manually, right?

I tried, but with no luck. Is a bullet tip not the best method? Turning the wheel clockwise means raising the POI, right? Any tips on how to make the bullets hit lower with the BUIS?

BTW, this was with 55 grain M193 only.

Any help would be great, thanks.

 

[1832]

A bullet tip can do it. Depress the detent with the tip and rotate the sight post counterclockwise, which raises the front sight and lowers the POI. A front sight adjustment tool (4 or 5 prong, which ever you have) can make the job easier.

 

[strangelittleman]

If what 1832 said doesn't help enough, you may need the taller front sight post, which available from Bushmaster and others. I don't know about the Troy rear sight but I learned this is so with the ARMS#40 rear sight so it may be so with other makers rear BUIS.

 

[Sylvan-Forge]

Front sight tools:
http://www.brownells.com/aspx/NS/store/ProductDetail.aspx?p=322&title=AR-15 SIGHT WRENCH&s=1546#1546

 

[Kentak]

It's useful to remember that the point of *impact* changes the same way as moving the rear sight, but the opposite way for the front sight. Therefore, you want to raise your front sight post.

And, yes, an AR front sight tool is very handy. Make sure you get one with the number of prongs to match the number of "holes" in your front sight post.

K

 

[rcmodel]

Screwing in, clockwise, raises POI.

Screwing out, counter-clockwise, lowers POI.

rcmodel

 

[W.E.G.]

Each click of an A-2 front sight post is worth 1.375 MOA.


A-2 sight click values - from Colt manual

 

[ny32182]

FWIW, I don't believe you are supposed to zero the elevation with the rear sight anyway. The A2 rear sight elevation is used for correcting the zero at range.