Muzzle velocity design. In a side by side comparison with the .50 BMG, the titanium round "of any caliber" released almost 28 times the energy of the .50 BMG, with only a 27% mean loss in momentum. Energy, in most cases, is what is lethal to the target, not momentum. In conventional guns, muzzle velocity is determined by the quantity of the propellant (burn speed, expansion), the mass of the projectile, and the length of the barrel. A slower-burning propellant needs a longer barrel to burn completely, but can, on the other hand, use a heavier projectile. A faster-burning propellant may accelerate
Zero-velocity surface Zero-velocity surface The zero-velocity surface is a concept that relates to the N-body problem of gravity. It represents a surface a body of given energy cannot cross, since it would have zero velocity on the surface. It was first introduced by George William Hill. The zero-velocity surface is particularly significant when working with weak gravitational interactions among orbiting bodies. In the circular restricted three-body problem two heavy masses orbit each other at constant radial distance and angular velocity, and a particle of negligible mass is affected by their gravity. By shifting to a rotating coordinate system where the masses are