Zero an M249 Machine Gun
071-312-4030
Conditions: Given an M249 machine gun on a live-fire range, or on terrain where the M249 can be fired safely; a 300-meter target located 300 meters from the firing position; and a 30-round belt of ammunition.
Standards: Using no more than 30 rounds, adjust the sights on an M249 machine gun to correct the sight picture, and cause a fired round to impact the target at the point of aim.
Performance Steps1.Set sights for initial firing.
a.Elevation. Using the elevation knob, index the known range (300 meters) to the target. Center the peep sight by rotating it clockwise (right) as far as it will go, then rotate it counterclockwise (left) five clicks (Figure 071-312-4030-1).
Figure 1. Sliding scale on sight.
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NOTE: The elevation range-scale wheel has range settings from 300 to 1,000 meters. The even-numbered range settings are on the left side of the scale wheel and the odd-numbered range settings are on the right.
b.Windage. Rotate the windage knob toward the muzzle until the peep sight is completely to the right, then rotate the windage knob back toward the buttstock 12 clicks to the left. This will place the peep sight in the approximate center of the sight (Figure 071-312-4030-1).
2.Assume a good, stable firing position (Figures 071-312-4030-2 and 071-312-4030-3).
Figure 2. Prone position, bipod-supported.
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Figure 3. Fighting position, bipod-supported.
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3.Fire a 3-round burst at the center base of the target. Note where the burst strikes.
4.Adjust sights so that the rounds impact the target area.
a.Adjust the sights for deflection. Determine if the center of the beaten zone is left or right of the target. Adjust the windage knob forward to move it right, or rearward to move it left (Figure 071-312-4030-4).
b.Adjust the sights for elevation. Determine if the center of the beaten zone is above (high) or below (low) the point of aim. Rotate the peep sight clockwise to lower it, or counterclockwise to raise it (Figure 071-312-4030-4).
Figure 4. Windage and elevation (peep sight) correction chart.
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5.Fire a confirming burst. If you miss the target, repeat Steps 3 and 4 until you hit the target.
6.Adjust the elevation scale to reflect the range to the target.
7.Record the zero. Once you have zeroed the weapon, record the elevation setting.
a.Deflection. Instead of recording the adjustments for the windage scale, just loosen the windage sliding-scale screws and align the scale so that the large index line is under the windage mark on the sight. Tighten the screws.
b.Elevation. Count the number of clicks (half turns) you have moved the peep sight away from the initial setting. For example, with a 300-meter zero--
(1)if you moved the peep sight two clicks (half turns) up, record "ZERO 300 UP 2."
(2)If you moved the peep sight two clicks (half turns) down, record "ZERO 300 DOWN 2."
Evaluation Preparation: SETUP: At the test site, provide all equipment and materials in the task condition statement.
BRIEF SOLDIER: Indicate the target and the range to the target. Tell the Soldier that he has 30 rounds to zero the M249.
1.Set the sights for initial firing. / —— / ——
2.Assume a good, stable firing position. / —— / ——
3.Fire a 3-round burst at the center base of the target, and note where the burst strike. / —— / ——
4.Adjust the sights so that rounds impact the target area. / —— / ——
5.Fire a confirming burst. / —— / ——
6.Adjust the elevation scale to reflect the range to the target. / —— / ——
7.Record the zero. Once completed, record the elevation setting. / —— / ——
Evaluation Guidance: Score the Soldier GO if all performance measures are passed. Score the Soldier NO-GO if any performance measure is failed. If the Soldier scores NO-GO, show the Soldier what was done wrong and how to do it correctly.
ReferencesRequired / Related
FM 3-22.68
TM 9-1005-201-10
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