Grazing fire is a term used in military science and defined by

NATO The North Atlantic Treaty Organization (NATO, ; french: Organisation du traité de l'Atlantique nord, ), also called the North Atlantic Alliance, is an intergovernmental military alliance between 30 member states – 28 European and two No ...

and the

United States Department of Defense The United States Department of Defense (DoD, USDOD or DOD) is an executive branch department of the federal government charged with coordinating and supervising all agencies and functions of the government directly related to national secur ...

as “Fire approximately parallel to the ground where the center of the cone of fire does not rise above one meter from the ground.” Grazing fire is often performed by machine guns. It is tactically advantageous when attempting to cut off an infantry ground assault or counter-attack.Army Field Manual No. 23-65
"BROWNING MACHINE GUN CALIBER .50 HB, M2" In grazing fire, the cone of fire does not exceed —the average height of a soldier—above the ground. When each bullet is fired, it will leave the barrel of the weapon at the axis of bore set from the angle of sight desired to strike the target area. The trajectory of the round should be constant as well as maximum ordinate. Maximum ordinate is the highest point of the trajectory, which is usually two-thirds the distance to the target from the weapon. Depending on the caliber of the round being fired and the slope of the terrain, as well as the distance to the target, the bullet will maintain a semi-flat trajectory. With

7.62×51mm NATO The 7.62×51mm NATO (official NATO nomenclature 7.62 NATO) is a rimless, bottlenecked rifle cartridge. It is a standard for small arms among NATO countries. First developed in the 1950s, the cartridge had first been introduced in U.S. service fo ...

ammunition, which is most commonly used with, for example, the M240 machine gun, the bullet will reach a distance of traveling at , before it begins a pronounced downward trajectory to the earth. Any distance beyond that range will be considered

plunging fire Plunging fire is a form of indirect fire, where gunfire is fired at a trajectory to make it fall on its target from above. It is normal at the high trajectories used to attain long range, and can be used deliberately to attack a target not susc ...

due to the arc (axis of bore plus angle of sight) needed to impact the target area. Grazing fire is so named because it cuts the vegetation low as though a herd of cattle had been grazing there. The optimal height of fire should be at knee height. In addition to keeping the enemy pinned down, anybody wounded or going to cover will fall into the line of fire, not out of it.

References

Military science {{mil-stub