pub fn free_recoil(inputs: FreeRecoilInputs) -> Result<FreeRecoilResult, String>Expand description
SAAMI free-recoil momentum balance (see module docs):
firearm_mass * V_recoil = bullet_mass * V_muzzle + charge_mass * V_gas,
FRE = 0.5 * firearm_mass * V_recoil^2, impulse = firearm_mass * V_recoil.