AR15 sight question

[MontanaMarine]

Have a Bushmaster Dissipator upper. 16" bbl, with carbine gas system, rifle length handguards, and rifle sight radius. Rear sight is detachable carry handle, with A3 style sight, with elevation drum from 300 to 600 yards.

Here's the thing, when I adjust the rear elevation to 3 minus 2, and zero at 200 yards via front sight elevation corrections, my front sight post is sticking up higher than the protective ears. I don't really want it to get 'polished' over time by touching things.

So is there a fix? Do I have the incorrect combo of front or rear sight?

Thanks, Shane

 

[Badshot308]

Re: AR15 sight question

Per Bushmasters website, that's the correct combo http://www.bushmaster.com/catalog_xm15_BCWA3S16D.asp Not sure what you mean by 3 minus 2. I have the same carrying handle on my 20" Bushmaster with A2 front sight. I have the rear elevation bottomed out on the 6/3 mark and the front sight post is .054" below the protective ears with a 100yd zero using M193. At 200, the load shoots just 2-3 inches low, so to zero at 200, my front post would even be deeper.

 

[MontanaMarine]

Re: AR15 sight question

By 3 minus 2 I mean I have the drum bottomed out, at 2 clicks below the 300 (3) yard setting.

 

[MontanaMarine]

Re: AR15 sight question

Maybe it's an ammo issue. I'm tossing 77s at 2650 fps. The extra "bounce" in the recoil might be lifting the muzzle a tad before the bullet gets out.

 

[Badshot308]

Re: AR15 sight question

OK, I understand. On my carrying handle, when the drum is bottomed out, it's right at the 300 (3) setting. I've shot Black Hills 77 SMK's out of my Bushmaster, but using the scope only and never the sights. You could try a 55 grain load or a different proven rear sight. I always thought that the bullet leaves the barrel before the recoil starts to act on the weapon. Thought I saw a high speed video showing that. Could be wrong about that. Just dug out two targets that I shot on 8-25-2010 with the 77 SMK. Those shot approximately 3.5" low as well.

 

[MontanaMarine]

Re: AR15 sight question

Thanks, usually I use a scope too, but now and then I like to dust off the irons.