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Old 01-27-2010, 12:22 PM
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ar15barrels ar15barrels is offline
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Tracking Test
You should test that your scope tracks properly.
This is also known as a "Box" test.

What you want to do is to go to the range and setup a nice clean LARGE piece of cardboard at exactly 100yds.
Make sure the cardboard is level left/right.
Setup a single target towards the bottom of the cardboard.

Verify that you are on a proper zero with the gun level left/right and fire a group on the target.
Mark the shots already on the target so you know which ones were already on that target.
Adjust your scope left 10moa or 3 mils.
Fire a couple rounds at the same target.
Adjust your scope up 15moa or 4 mils.
Fire a couple rounds at the same target.
Adjust your scope up another 15moa or 4 mils.
Fire a couple rounds at the same target.
Adjust your scope 20moa or 6 mils right.
Fire a couple rounds at the same target.
Adjust your scope back down 15moa or 4 mils.
Fire a couple rounds at the same target.
Adjust your scope back down another 15moa or 4 mils.
Fire a couple rounds at the same target.
Finally, adjust your scope back to the left 10moa or 3 mils.
Fire a couple rounds at the same target and check to see that they landed within the original group that you shot.

If your scope is tracking correctly, you should end up with a rectangle on the target frame that's 20.9" wide and 31.4" tall if you are shooting a scope with MOA knobs.
If your scope is tracking correctly, you should end up with a rectangle on the target frame that's 21.6" wide and 28.8" tall if you are shooting a scope with MIL knobs.

The rectangle should be formed perfectly square and level.
If the rectangle has good square corners, but the whole box is angled, then your scope is probably not mounted straight.
If the rectangle looks more like a parallelogram, then you have a scope problem.
If the rectangle does not have square corners, you have a scope problem.
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Last edited by ar15barrels; 04-06-2010 at 10:08 PM..
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