In the absence of other means, the gunner can lay the machine gun for and engage predetermined targets using field expedients. (These methods are less effective than the traversing bar and T&E (Traversing and Elevating) mechanism methods.)
1. Base Stake Technique - Use a base stake to define sector limits and provide the lay for the Final Protective Line (FPL) or predetermined targets along a primary or secondary sector limit. This technique is effective in all visibility conditions.
• Define the sector limits by laying the gun for direction along one sector limit and emplacing a stake along the outer edge of the folded bipod legs. Rotate the legs slightly on the receiver so you can take up the “play.” Use the same procedure to place a stake on the opposite sector limit.
• Lay the machine gun along the FPL by moving the muzzle of the machine gun to a sector limit. Adjust for elevation by driving a stake into the ground, so that the top of the stake is under the gas cylinder extension. Allow a few mils of depression to cover irregularities in the terrain.
• Lay the machine gun to engage other targets within a sector limit in a primary sector the same as previously described, but keep the elevation fixed.
2. Notched-Stake or Tree-Crotch Technique - Use the notched-stake or tree-crotch technique (Figure 5-24) with the bipod mount to engage predetermined targets within a sector or to define sector limits. This technique is effective during all levels of visibility, and it requires little additional material.
• Drive either a notched stake or tree crotch into the ground where you expect targets to appear. Place the stock of the machine gun in the nest of the stake or crotch. Adjust the weapon to hit the selected targets and to define your sector limits. Note: If notched stakes and crotches are unavailable, use tent poles. You need four poles for the left and right limits and extra poles for target areas. Drive two poles in the ground in the shape of an "X," and then place the stock in the "X."
• Dig shallow, curved trenches or grooves for the bipod feet. The trenches let you rotate the bipod feet as you move the stock from one "X" or stake to another.
3. Horizontal Log or Board Technique - Use this technique with the bipod or tripod mount to mark sector limits and engage wide targets. This technique is also good in all visibility conditions, and it works best on level terrain.
a. Bipod-Mounted Machine Gun - Place a log or board beneath the stock of the weapon so the stock can slide across it freely. Dig shallow, curved trenches or grooves for the bipod feet. This lets you rotate the feet as you move the stock along the log or board. To mark the sector limits, notch or place stops on the log or board. When you fire,
use the bipod firing position and grip.
b. Tripod-Mounted Machine Gun - Place a log or board beneath the barrel, positioning it so that the barrel, when resting on the log or board is at the proper elevation for grazing fire. Marks the sector limits, when appropriate, as described for the bipod in the preceding paragraph. Use this technique only if you have no T&E mechanism.