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aftershock
02-27-07, 19:24
i just got my first ar and i have no clue how the zeroing process goes can someone try to explain it to me.....i have a RRA A2

Robb Jensen
02-27-07, 21:38
This is my zero which is essentially a Santose zero modified a little.



How to battlesight zero an AR rifle, 50yd/200meter method

Rear sight should be at 8/3 -2 clicks (this is two clicks below the 8/3 mark and the sight should bottom out). Note removable A3 type sights are marked 6/3 (rather than 8/3. If there is a 6/3 on the elevation drum then the sight needs to be set at –4 clicks (instead of –2). Most factory assembled rear sights don’t allow the rear sight to work this way BUT it is easily corrected by the following:
1. Flip the rear sight back to the unmarked aperture (the small one). This will reveal a hole in the top of the rear sight.
2. Rotate the sight wheel all the way down so that it bottoms out. It will probably be exactly at 8/3 (or 6/3).
3. Using a 1/16" Allen wrench, loosen the screw (under the revealed hole) in the sight wheel 3 full turns. Leave the wrench in the screw.
4. Rotate the bottom half of the sight wheel two clicks clockwise if your sights marked 8/3, four clicks its marked 6/3. This will raise the sight body if you look at it while you're turning it.
5. Tighten the Allen screw, remove the wrench, and confirm the sight bottoms out at -2 clicks BELOW 8/3 (if you have 8/3), -4 clicks if you have 6/3. If not repeat the procedure until it's absolutely right

If you’re running a rear sight without elevation adjustments (i.e. Larue, ARMS, Troy, or if you have an A1 sight) then just flip to the smallest aperature, center it up in the sight and head to the range.
Now to the range:
• Small aperture, nose to charging handle.
• Distance is 50 yards (150ft). (you can start at 25yd, impact will be 1-1.5” lower than your point of aim, then move to 50yds).
• Point of aim (POA) should be point of impact (POI) at 50yds.
• Remember you're adjusting the FRONT SIGHT for elevation, not the rear, and that each click changes POI 1/2" (actually a little more) at 50 yards. You won't get it closer than that.
• You're done. Leave the sight in this position for 99.9% of your shooting.
• If you have to shoot targets you KNOW are 300 meters away or more, just click to the right number on the sight.
• If you're patrolling or shooting at distances less than 50yds, set the rear sight to 8/3 (of 6/3) and snap the aperture forward to 0-2 or larger setting. This will provide the same trajectory as above but with a larger, this will be much faster and easier to see thru.
• If you have an optical sight (magnified scope, Aimpoint, Eotech etc) zero it to 50/200 as well.
• This battlesight zero is valid to 200 meters for most ARs including the 20”, 16”, 14.5” models due to the offsetting influence of higher muzzle velocity in the rifle being offset by the longer sight radius that moves bullet strike less per click. 10.5” and 11.5” ARs will be close but not exact. This zero gives a nice flat 200 meter zero which has the happy coincidence of an initial trajectory cross-over at 50 yards, a distance available on almost all civilian ranges including some indoor ranges (like the NRA Range). This makes it easy to achieve a 200 meter battlesight zero without recourse to surveying your own range. If 200 meters is available you can fine-tune the zero at the real distance. And should when you get the chance. Using this method you will never be off elevation wise more than 2” from the muzzle to 200meters from your line of sight.

aftershock
02-28-07, 00:38
thank you....just what i needed