# Can shotguns recoil really boost you in midair?

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I was wondering for a while, I’ve been playing some movement FPSs so that is what sprouted this idea.

In: Physics

I’m not a math guy, but I do love my shotguns. The recoil from even a 10 gauge wouldn’t be enough to change much as far as keeping you in the air longer or making you jump further. However, it would throw you off balance and increase your chances of injury upon hitting the ground.

No. For it to “boost you” it’d have to be able to similarly “boost” someone away from you. Despite what movies show you, people don’t get blown away when shot.

Yes, but also no. Firstly, there is nothing special about shotguns here, any gun follows the same basic principle, when fired a bullet is pushed forward, and the gun is pushed back with equal force. However guns don’t actually have that much total force behind them, bullets only move so fast because they are so light, so you aren’t gonna get much push. For example an AK-47 generates about 6 newtons of force per bullet fired. It takes about 10 newtons of force to lift a 1kg object.

xkcd that gives a better answer to a slightly different question (Is it possible to build a jetpack using downward firing machine guns?), and goes over the math better linked below.

[https://what-if.xkcd.com/21/](https://what-if.xkcd.com/21/)

In theory yes. The case in point would be the A-10 warthog’s gun. If it fired too long of a burst, the aircraft risks stalling due to the immense recoil of the massive gun coupled with the extremely high rate of fire.

So in theory, if you took a 10 gauge shotgun and made it feed from an electrically driven motor and 10 rotating barrels at 10k rounds per min, and you strapped a 6 lbs baby to it, my assumption is that baby would go sailing.

If you weighed the same as the piece of paper the cartoons are drawn on, sure. For even a small human being (one old enough to safely operate a gun), no. The force of kickback is usually less than 15lbs.

Artillery could be a different story, but you’re also not generally shouldering that.

Basically, no. You can get hurt using a shotgun if you try to hip fire it or if the butt of the stock isn’t resting firmly on your shoulder, but it is not going to launch you backwards like you see in some films, nor will it launch a person being shot backwards.

No, not to any significant degree. For it to provide enough force to carry you even a little? It would need to be so much recoil it would knock you on your ass when trying to fire it normally.

Guns aren’t too dissimilar from thrusters you expell some mass in one direction and momentum is conserved which kicks you in the opposite direction.

An AK-47 bullet 7.62×39mm has a muzzle velocity of 710 m/s and a mass of 8g (according to Google) which gives us a momentum of 710 m/s × 0.008 kg = 5.68 kgm/s.

Say a human with 80 kg mass sliding at v velocity on a frictionless table would fire a bullet in the sliding direction, at what v would they stop? So p_0 = m_h × v.

p_0 = p_1 + p_b

p_1 = m_h × 0 as they stopped

p_b = 5.68 kgm/s

5.68/80 m/s = v = 7.1 cm/s = 0.2556 km/h

So of course there is knockback but you can see hoe its not that much.