Guns in space!

[Dean Watson]

If I don't get any replies with a title like that I shall be highly surprised.  Anyway, to quote Jerome K Jerome, idle thoughts of an idle fellow;

 

So, Newtonian physics aside, given that a bullet requires some sort of combustion to fire from a gun, would an ordinary pistol/rifle and bullet (and I presume that a bullets make up is on the whole the same for most stuff - don't shoot me if i'm wrong and you're a gun nut) fire in the vacuum of space - and I suppose come to think of it, given muzzle velocity etc how effective a 'rocket'  (every action and gubbins) would it be?

 

Discuss... (and enjoy of course).  Could look up much of this myself but its more fun throwing it out there.

[+Bino-viewer]

The short answer is yes, a gun / rifle would work fine in space.

Oxygen for combustion is not required.

Ammunition is fired by the combustion of the propellant, and this has an oxidising agent added into the mix,

so no, it would not be affected by the vacuum of space.

 

On Earth, ballistics is greatly affected by air resistance once a bullet is fired.

No issues up in space. 

Regarding how far a bullet would travel, i'd say if it was fired in deep space, its velocity would remain unchanged and it would carry on indefinitely.

If you were at the ISS and were doing a spacewalk and fired a gun, i'm assuming gravitational forces would eventually come into play, and bring the bullet

back down and burn up in the Earths atmosphere.

 

Btw, i've always been fascinated in ballistics, guns, rockets etc

And if i lived in the US, i'd almost certainly be a gun owner.

 

Edited May 4, 2016 by Bino-viewer
typos

[Doc]

You may have to consider how cold space is. Is it cold enough to cause fractures in the gun, what will happen to the grease/lubricants in the gun, will it freeze and stop the gun working.

[tuckstar]

Would you not find yourself disappearing in the oposite direction due to the 3rd law!?

[Dean Watson]

Hi tuckstar, yes, that was kind of my question - I cant be bothered (!) to work out the maths but was wondering how much of a propellant effect a fired gun would have on the gunman.  I suppose it would always depend on the muzzle velocity of the gun and I don't know if they are all much the same or wildly variable (Or, hang on, how efficient a rocket motor would a gatling or mini gun be?).  Cant help but think the space agencies are missing a trick here...

[Doc]

12 minutes ago, tuckstar said:

Would you not find yourself disappearing in the oposite direction due to the 3rd law!?

 

Not if you are secured to something. 

 

Because your mass is much greater than the bullet you will drift backwards in the opposite direction a lot slower then the speeding bullet.

[tuckstar]

30 minutes ago, DeanWatson said:

Hi tuckstar, yes, that was kind of my question - I cant be bothered (!) to work out the maths but was wondering how much of a propellant effect a fired gun would have on the gunman.  I suppose it would always depend on the muzzle velocity of the gun and I don't know if they are all much the same or wildly variable (Or, hang on, how efficient a rocket motor would a gatling or mini gun be?).  Cant help but think the space agencies are missing a trick here...

Yep there's nothing we need more than hundreds of tiny bits of metal orbiting the earth!?

[Smithysteve]

Ok, theoretically it would work, but if you were in orbit around the earth and miss your target, and the bullet goes off in an orbital path, you could eventually end up shooting yourself - if and when it comes back around ... ouch!!!? That's called Murphy's law...

recoil would be the same as on earth. But at least you wouldn't need to wear ear defenders! 

Edited May 4, 2016 by Smithysteve

[BAZ]

I suspect you would have a greater effect regarding the discharge of the gun. Not only are you projecting the bullet out of the barrel, but the blast from the discharge is effectively a short duration rocket motor, aiming the blast away from you, so it's not only the effect of the reaction but also the energy of the initial blast being directed as well, which would have a much greater effect than just the equal/opposite reaction and smaller mass of the bullet. I suspect you could be disappearing faster than the bullet.

Edited May 4, 2016 by BAZ

[Perkil8r]

If you were in orbit around Earth and shot in the direction of that orbit the bullet would initially move to a higher orbit. The gunman would descend into a minutely lower orbit due to the minute change in his orbital velocity. The bullet would though still drop back toward Earth in time. At 250 miles up, the altitude of ISS, there is still enough atmosphere to have an effect on an object orbiting, hence why the ISS is often boosted slightly to keep it in a stable orbit. The bullet would not have the luxury of that intermittent boost so would drop back toward Earth.

 

Shot in the opposite direction to the orbital path the bullet would assume a much lower orbit, the gunman would move minutely higher. The bullet would drop to Earth much sooner than if fired in the same direction as the orbit.

 

All of this is of course futile procrastination though since the gun would never be allowed on the spacecraft in the first place. Have you not seen what a disaster that almost caused in the motion picture "Armageddon" ?

[BAZ]

Yeah, why do you need a gun when you are perched on a 3000 ton bomb!

[Perkil8r]

Remember folks, guns don't kill people, rappers do.

[Dean Watson]

We are now so far of topic its not true! Moderator! Moderator!  Actually, if this were another forum of my acquaintance they'd have probably shut this thread by now for some spurious reason... You know, the one with a skin that looks like this one...

[Daz Type-R]

No idea which one you mean.........  

[Dean Watson]

No, it sounds nothing like store browsers scrounge... Nothing like it I said!

[tuckstar]

2 hours ago, DeanWatson said:

We are now so far of topic its not true! Moderator! Moderator!  Actually, if this were another forum of my acquaintance they'd have probably shut this thread by now for some spurious reason... You know, the one with a skin that looks like this one...

And that's why some of us are here!!

[Dean Watson]

Me too actually!  Cant remember what it was now but some silly draconian judgement- I asked for the account to be closed.