Sir Issac Newton's Three Laws of Motion. Nothing more is relevent
The handgun recoils upward only because the axis upon which the explosion occurs is above the grip of the weapon, which is where you hold it. The gun would fly straight back if you were not holding it by the grip; your grip keeps the bottom of the gun relatively stationary while the upper portion (along the axis of the explosion) is forced rearward, which causes the gun to tilt from recoil. This is why firearms which have the bore axis down closer to the grip (such as the Chiappa Rhino), have less muzzle flip.I can see how someone could think it happens after the projectile leaves the barrel as the barrel points pretty skyward yet the projectile goes straight ahead, therefore it must have left before the barrel headed skyward
Well, the rearward acceleration of the gun ends very quickly, yes. But the peak force on your shoulder doesn't occur until significantly later, when the recoiling gun is being decelerated and your shoulder is being shoved backward. And while our perceptions do lag a little behind reality, the acceleration impulse and the peak of the deceleration impulse *are* separated in time by a significant (and probably very perceptible) amount.Nerve signals travel ~ 100 m/s. The impulse from a rifle has a duration in hundredths of a second. In short, you're perception lags behind the forces, which peak as soon as the bullet is no longer accelerating down the barrel, so that it only seems that the majority of recoil occurs after the bullet leaves the barrel.
F=M(rifle) x A(rifle) = m(bullet) x a(bullet) --> A=(ma)/M=a(m/M)
The impulse is the integral of the force with respect to time over the time it takes the bullet to accelerate down the barrel
If a projectile struck a person with enough power to throw them say through a glass window in front of the bar in an old western, the shooter would be knocked down as well from the recoil
Finally, someone who understands what is really happening.That's all smoke and mirrors, recoil is all due to the gravitational forces generated by the spin of the bullet trying to pull the sun out of it's orbit around the earth.
Posted by Freedom_fighter_in_IL: [If a projectile struck a person with enough power to throw them say through a glass window in front of the bar in an old western, the shooter would be knocked down as well from the recoil [is]]Not entirely correct Hatter.
You have to add in the speed and weight of the projectile to get Kinetic energy. Example, if you get hit with say a .45acp point blank while wearing an older style Kevlar vest, you end up with broken ribs. Now, you cant tell me that the recoil from a .45 will bust your ribs.
In point of fact, kinetic energy in handgun projectiles contributes to killing effectiveness only insofar as it affects penetration. The bullet penetrates the body of the target and damages organs or causes bleeding or both.Now granted yes you are correct in the statement that the target wouldn't be thrown back 20 feet like you see in the movies, but when you factor in the kinetic energy formula, you end up with much more power on the travel side than the recoil side. If this were not the case, a firearm would be useless as it would kill on both sides.
What would knock someone backward is momentum, not energy; basically, energy breaks things, momentum moves them. Momentum is the same on both ends of the gun (actually a little greater on the shooting side of things than the receiving side, because the propellant gases don't typically reach the target), but far more energy is delivered to the target than is delivered to the shooter.Not entirely correct Hatter. You have to add in the speed and weight of the projectile to get Kinetic energy. Example, if you get hit with say a .45acp point blank while wearing an older style Kevlar vest, you end up with broken ribs. Now, you cant tell me that the recoil from a .45 will bust your ribs. Now granted yes you are correct in the statement that the target wouldn't be thrown back 20 feet like you see in the movies, but when you factor in the kinetic energy formula, you end up with much more power on the travel side than the recoil side. If this were not the case, a firearm would be useless as it would kill on both sides.
What would knock someone backward is momentum, not energy; basically, energy breaks things, momentum moves them. Momentum is the same on both ends of the gun (actually a little greater on the shooting side of things than the receiving side, because the propellant gases don't typically reach the target), but far more energy is delivered to the target than is delivered to the shooter