Meplat
From Wikipedia, the free encyclopedia
The meplat (from the French word "méplat" meaning "flat surface of a cylinder") is the technical term for the flat or open tip on the nose of a bullet. The shape of the meplat is important in determining how the bullet moves through the air. In particular the size and shape of the meplat has a significant effect on the ballistic coefficient of a bullet.[1]
Trimming the meplat (cutting the tip of the bullet, thus increasing its area[2]) decreases the bullet's ballistic coefficient, increasing drag, and making it more susceptible to wind drift. So even though the grouping will be tighter, the time of flight and wind drift will be slightly greater.[3]
Pointing the meplat (reducing its area) involves pressing the bullets into a special die. This decreases the size of the meplat which increases the ballistic coefficient, which reduces drag, time of flight, and wind drift of the bullet.[3][4] Some target shooters sort their bullets by weight, point their bullets, and then trim them to the same meplat width to ensure the greatest possible consistency.[3]
Meplats are often used to increase the bullet's wounding ability.[5]
The shape of the nose of an axisymmetric projectile that gives it the least possible aerodynamic drag at hypersonic speeds always has a meplat, the diameter of which depends on the length of the nose.[6]
