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How to Zero your Scope - "2 Shot System"

How to Zero your Iron Sights

A zero is the alignment of the sights with the bore of the rifle so the bullet will impact on the target at the desired point of aim. When the aim, the sights, and the bore coincide on the same point, it is called the zero. There are two zero ranges, near and actual. These are the two locations that the bullet crosses the line of sight.

Step 1: Determine your Zero Distance: 50 Meters

Firing ranges should have known distances marked by stakes, signs or lines on the ground. Be sure to note whether it is yards or meters. While the difference between yards and meters is relatively small, knowing it may save you some ammunition.

If you are using a range that is not marked, you'll have to pace, measure or laser range find the distance yourself. In this example it's 50 Meters.

Step 2: Fire 3 Round Group.
We are looking for a good tight shot group. Adjustments are made from an estimated center of the shot group.

Firing Pattern 3 Round Group

Step 3: Measure for Vertical Correction

Measure Bullet Holes for Vertical Adjustment

Step 4: Measure for Horizontal Correction

Measure Bullet Holes for Horizontal Adjustment

MOA Defined:

A minute of angle (MOA) is an angular measurement equal to 1/60 of 1 degree of arc. Its size increases uniformly over the range, but its value stays the same. At 100 meters the true value of an MOA equals 1.14 inches this can be rounded down to just one inch; one MOA at 200 meters equals 2.29 inches but can be rounded down to 2 inches; and at 300 yards, three inches; and so on.

Thus a sight adjustment error of 2 inches at 100 yards becomes a 10 inch error at 500 yards and a 20 inch error at 1000 yards.

Step 5: Look up your inch or centimeter value for

your MOA/CLICK at your zero distance(Meters)

Step 6: Adjust elevation settings

Number of clicks of elevation = Measure of Vertical Correction Needed ÷ Inch or CM for your MOA/Click at your zero distance

Example: 5.125 ÷ .57 = 8.99 round to 9 clicks up.

Step 7: Adjust windage settings
Number of clicks of windage = Measure of Horizontal Correction Needed ÷ Inch or CM for your MOA/Click at your zero distance

Example: 3.25 ÷ .57 = 5.70 round up to 6 clicks to the left.

Step 8: Repeat steps 3-8 until your shot group coincides with your point of aim

Adjusting Shot Group to Point of Aim

If it takes more time then do it. Better to be spot on then miss opportunities at greater distances.

Number of questions: 1
0 0
Your graphic in Step 5 says to look up your MOA/Click at the zero distance. My question is, is that number consistent for all caliber and weights of bullets as it is shown in the chart in Step 5 or is it ammo specific. If it is ammo specific how do I find that info for the specific ammo I want to use ?
EdN. August 6, 2017 11:46 PM
Answers
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Ammo specific. You can generally find ballistic profiles on ammo mfgr websites for your particular ammo. At moderate ranges you’ll be close, but longer shots will vary a lot. Document your zeros for each type ammo you have and correct your turrets accordingly. Then shoot to confirm.
Jama February 11, 2021 2:38 PM
0 0
This zero method is consistent with the particular ballistic profile for the ammo used during adjustment. Another type ammo with a different ballistic profile i.e. different projectile weight, powder load, shape, etc. will have to be accounted for and adjusted. Also, the shooting conditions , wind, relative elevation of target are assumed to be the same for zero and will need to be compensated for on the fly for every shot.
Jama February 11, 2021 2:28 PM