Manual

25 METER ZEROING PROCEDURES (continued)…
4.) Now rotate the elevation knob "up" one click past the 300-meter mark. From this point on, the
elevation knob should not be moved. Any changes in elevation required in the following zeroing
steps are made to the front sight post only.
5.) Carefully aim and fire at the center of the target bull's-eye.
6.) If your shot group is not in the center of the bull's-eye, use the squares on the target sheet to
calculate the required "clicks" necessary to move your next shot group into the bull's-eye.
Remember - any changes in elevation are made by moving front sight post only!
7.) In order to raise your next shot group, rotate the front sight post clockwise. One click of
the front sight post will move the the bullet strike one vertical square on the target sheet.
In order to lower your next shot group, rotate the front sight post counter-clockwise. One click
of the front sight post, as above, equals one square.
Changes in windage are made with the windage knob. Three clicks will move the strike of
the bullet one horizontal square on the target sheet.
In order to move the shot group to the left, turn the windage knob counterclockwise.
In order to move the shot group to the right, turn the windage knob clockwise.
8.) Carefully aim and fire another group at the center of the target bull's-eye.
9.) Repeat Steps 7 through 9, if required.
10.) If your group is on target, your sight is now "calibrated." To place your actual 300-meter zero
on the rifle, you must rotate the elevation knob one click "down." (The range scale's 300-meter
mark should now be aligned with the mark on the rifle's receiver.)
UNMARKED
APERTURE
APERTURE
MARKED L
EARLIER
A1 ROUND
SIGHT POST
FIVE
NOTCHES
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A1 Type Rifles have sights that differ a bit from the later A2 Style.
The A1 REAR SIGHT Has two apertures for differing ranges but does not offer any mechanical
means of adjustment for elevation
• Use the unmarked aperture for targets from 0 - 300 meters.
• Use the aperture marked L for targets from 300 - 400+ meters.
The A1 FRONT SIGHT - Has five notches of elevation per revolution (instead of the four
notches found on A2 square post type front sight - Bushmaster only uses the A2 type Front
Sight Post in its current production models).
1.) Battlesight zero is that setting on the Rifle's sights which will cause the point of aim and
strike of the bullet to be the same at 250 meters.
2.) When using the L-marked aperture, the path of the bullet will cross the line of sight at 25
meters. Hence, zeroing is now conducted with point of aim and point of impact being the same
(see chart on next page).
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A1 TYPE RIFLE SIGHTS - DIFFERENCES & ADJUSTMENTS…