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ChibiPaw
03-14-2009, 2:30 PM
So there were plenty of topics rather ammo would operate in the vacuum of space. But just ought of random stray thoughts.

Bolt action of course would not be an issue. But would semi auto firearms operate in space? As in round expelled, action cycled, shell expelled, and so on..

I'm thinking anything recoil only based would probably not work. eg: glock's etc.
But what about gas based system like the AR or AK platform? Would internal springs operate?

Condition would be the following:

Any semi auto pistol or rifle.
No atmosphere.
No gravity.
Person is floating, pulling the trigger. neither firearm or the person is attached to any objects.
Bill Nye may be present.

fusionstar
03-14-2009, 2:35 PM
the propellant in ammunition has its own oxidizer. so yes it will work in space.
The recoil impulse is too fast, I would think even a glock in space would work. but limp wristing a glock in space is a no no. Even on land its a no no.

ChibiPaw
03-14-2009, 2:43 PM
the propellant in ammunition has its own oxidizer. so yes it will work in space.
The recoil impulse is too fast, I would think even a glock in space would work. but limp wristing a glock in space is a no no. Even on land its a no no.

I was thinking the recoil would instead racking the slide, would simply be transfered to the entire gun, and on to the person.. Oh yea, I would guess limp wrist would be really bad. But I didnt think the fast recoil impulse would not make a difference in a zero G environment. Then again, maybe you're right.

rabagley
03-14-2009, 2:52 PM
The guns would work just fine, but you'd have to deal with the momentum transfer one way or another.

You may find that if a gun is left in vacuum for a long time that the lubrication will evaporate and metal-metal contact points may become vacuum welded together, which can cause severe stiction (various ftf, fte, issues) or even catastrophic failure.

Sam
03-14-2009, 3:02 PM
The bullet would theoretically travel forever in one way and the person would travel forever in the opposite way...that is until either one of them was sucked into a blackhole, the gravity pull of a planet, sun etc.

NeoWeird
03-14-2009, 4:20 PM
It's funny how people think once they are in space gravity stops effecting them.

Some Guy
03-14-2009, 4:44 PM
It's funny how people think once they are in space gravity stops effecting them.

I think its funny how your post is condescending and uninformative.:rolleyes::rofl:

Teletiger7
03-14-2009, 4:53 PM
Maybe in outerspace you can use firearms as a form of propulsion.

Experimentalist
03-14-2009, 5:48 PM
The OP raises an interesting question; there are enough differences between "space" and earth to make the answer not immediately obvious.

First, one should define "space". I suggest such a definition might be a microgravity environment such as you find in orbit around Earth, with breathable atmosphere optional (inside a capsule or outside). There are a couple of physics principles at work that I think help explain why semi-auto weapons will function in this environment.

First, while an object in microgravity is nearly weightless, this does not change the principle of inertia. Newton's first law of motion says an object at rest tends to stay at rest, and an object in motion tends to stay in motion along a straight line of travel. This effect is independent of gravity. In other words, even though the gravitational force is negligible the inertia of matter is unchanged.

This is important to the operation of firearms because the effects of gravity (and atmosphere) are not important to this operation. The resistance of the gun - shooter system to acceleration (it's inertia) allows something for the recoil springs to press against. Likewise, the inertia of the bullet (along with friction forces in the barrel) allow the propellant gasses to press against the bullet, and on the slide. This is also why a gas-operated firearm will function in space; the bullet inertia / friction allows the propellant gasses - which are confined to the gas system while they do their work - to cycle the arm. (ETA: Gas impingement systems like that found in the M-16 / AR-15 series firearms may require a bit of tuning to work well in a vacuum. This is because the gas may escape the system faster than it would on earth, possibly resulting in a short stroke of the bolt carrier).

This is also why "limp-wristing" a semiauto gun causes problems with proper cycling. The gun needs a proper "push" from the shooter to function. In a microgravity environment the shooter would be well served to properly reinforce his position before pulling the trigger, lest they find themselves moving in an unfortunate direction.

Rabagley raised a clever point about the effects of a vacuum on lubricants. In the case of a gun left floating by itself in orbit around earth you have to wonder what effects extreme heat, cold, and radiation will have on the metals and propellants over time.

Pugster
03-14-2009, 5:50 PM
If a Glock can function underwater then it can in space too. Would be interesting to the effects of recoil in space.

audihenry
03-14-2009, 6:09 PM
They would all function. Being in space would make no difference in recoil, blowback, and gas operations.

bohoki
03-14-2009, 7:18 PM
yea why would gravity matter my guns all work upside down and gangsta style

as to 100 yard accuracy it would always be shooting high as there is no drop in space

i wonder if the floating granules in the case would ignite quicker though maybe slightly increasing pressure

i used to worry about bullet push out due to the 14 psi here on earth and the 0 in space but it takes more than 14 psi to pull a bullet

there would be a problem firing a gun say on venus as the pressure of 1300 psi would cause all the bullets to be pressed into their cases and may cause feeding issues

lasereye
03-14-2009, 8:23 PM
Sounds like a good " Myth Busters " show. :clap:

Gunaria
03-14-2009, 8:27 PM
Sounds like a good " Myth Busters " show. :clap:

The most expensive one ever!

Gunaria
03-14-2009, 8:29 PM
Also think about this, shooting a firearm in a enclosed oxygen rich environment is a big no-no.

Jpach
03-14-2009, 8:32 PM
I was thinking the recoil would instead racking the slide, would simply be transfered to the entire gun, and on to the person.. Oh yea, I would guess limp wrist would be really bad. But I didnt think the fast recoil impulse would not make a difference in a zero G environment. Then again, maybe you're right.

With that logic, wouldnt a recoil operated gun not work on earth when falling from the sky or jumping? The shooter is still keeping the frame mostly still. I would imagine it would still work. Things still move in space.

Decoligny
03-14-2009, 9:41 PM
I was thinking the recoil would instead racking the slide, would simply be transfered to the entire gun, and on to the person.. Oh yea, I would guess limp wrist would be really bad. But I didnt think the fast recoil impulse would not make a difference in a zero G environment. Then again, maybe you're right.

You have to understand that the lack of gravity and atmosphere does not equal the lack of inertia.

A stationary object will stay stationary until acted upon by an outside force.

The stationary object would be the gun, the hand holding the gun, the body that the hand is connected to. The only thing different that firing a gun on the ground is there is no gravity holding you to the floor, and the presence of atmosphere.

Imagine falling in an elevator. You are falling at a rate that causes you to be weightless. Would you still be able to fire the gun and have it operate as designed? YES. However when you pulled the trigger, the force would push your body slightly away from the direction of the bullets travel. There would still be more than enough resistance for the action to work properly and for the gun to cycle. The absence of air would only allow the bullet to travel for a longer distance without slowing due to air resistance.

56Chevy
03-14-2009, 9:54 PM
Guys, it's outer space. You'd be using ray guns designed by little green guys. Either that, or the conversion kit for Glocks. Gaston Glock designed the kits with the help of aliens. I heard all about it when George Noori talked to Erich von Däniken.:TFH:

ty423
03-14-2009, 10:38 PM
Also you probably won't hear anything since there is no air for the sound to travel...

ricknadine1111
03-14-2009, 10:40 PM
With all you brains out there it's a wonder why the US Government has spent millions on that laser system.

7x57
03-14-2009, 10:46 PM
Must...not...show...geek...credentials...

OK, fine. As pointed out, very little changes for a firearm in space. It is possible that some weapons depend on gravity for proper feeding, though I think most don't. Supposedly some push-feed bolt-actions aren't reliable upside down, so maybe they would have an issue in space. The only answer is to have an upside-down range session and find out. :D I'd say anything that functions upside down and on its side should be more than fine in space.

Depending on what I'm wearing and how much exposed skin I have, I'd sort of not like to be in a small metal-walled chamber when a lot of hot metal cylinders go bouncing around at high velocity in weightlessness. I want all my buddies who might fire near me to carry revolvers. :-)

The point about lubricants and vacuum welding is by far the best insight in the thread. I suppose it wouldn't be limited to the gun either. I wonder what happens when you use some old ammo and the bullet jacket has welded to the case mouth? Maybe not so good if the ammo is loaded hot, at least as bad as having the bullet forced up against the rifling. :eek:

I think there is a solution for the lubricant problem at least, besides looking for greases suitable for use in vacuum. Craig Boddington recommends bolt-action rifles for hunting polar bears on the arctic ice because they work well completely dry, which he says is better than any lubricant in extreme cold. That sounds good, except the cleaner the metals the better I imagine they'd vacuum weld. :-( Perhaps better to look into vacuum greases after all.

I also wonder if there would be problems with powder aging due to outgassing in vacuum, but I'm not enough of a chemist to know. Primers should be fine. Though it's not an aging test, I believe my wife has actually fired primers in vacuum in her lab.

7x57

trashman
03-14-2009, 10:52 PM
I also wonder if there would be problems with powder aging due to outgassing in vacuum, but I'm not enough of a chemist to know.


I think that this is probably the biggest hurdle - ammunition has plenty of gas in the sealed casing, and I wonder if the pressure differential would damage every round in some way...if not just "ease" the projectile out of the casing, or damage the crimp...

--Neill

7x57
03-14-2009, 11:37 PM
I think that this is probably the biggest hurdle - ammunition has plenty of gas in the sealed casing, and I wonder if the pressure differential would damage every round in some way...if not just "ease" the projectile out of the casing, or damage the crimp...


So let's think. A .45 round (about the largest caliber we'd expect to encounter, given that there are no elephants or cape buffalo in space) has a base area of about 0.16 in^2, so an atmosphere of pressure in the case would exert less than 2.5 lbs of force on the bullet. I guess that might bother some handloads, if the crimp is weak. I know I've loaded plenty of rounds for a bolt-action rifle that were only held in place by neck tension, but I could have crimped them if I'd had a reason to. Semi-autos have to deal with feedramp setback already, so I expect them to be able to take more force than that.

Plus factories have plenty of tricks we don't do, such as using adhesive on the bullet. If they want it to work in space there will be no problem.

7x57

TheBundo
03-15-2009, 2:34 AM
Whenever I go out to space, I always take my revolver and lever action carbine. I wouldn't take a chance on the semi-auto. Plus the Zorlons are intimidated by the Lever-Action, as The Rifleman broadcasts are just beginning to reach them

trashman
03-15-2009, 8:33 AM
So let's think. A .45 round (about the largest caliber we'd expect to encounter, given that there are no elephants or cape buffalo in space) has a base area of about 0.16 in^2, so an atmosphere of pressure in the case would exert less than 2.5 lbs of force on the bullet.


The math doesn't lie -- excellent point.

--Neill

fusionstar
03-15-2009, 9:34 AM
if water can get in my rounds, air can get out ;)

56Chevy
03-15-2009, 11:09 AM
Whenever I go out to space, I always take my revolver and lever action carbine. I wouldn't take a chance on the semi-auto. Plus the Zorlons are intimidated by the Lever-Action, as The Rifleman broadcasts are just beginning to reach them
How do you pull the trigger with the big space gloves on?

dixieD
03-15-2009, 11:18 AM
The best thing about space, far from Earth is that you would get a true flat trajectory, and you would have terminal velocity (at target not to be confused with terminal velocity) that is the same as muzzle velocity. Imagine 1897 ft-lbs of energy at 1000 yards distance with a 308!

TheBundo
03-15-2009, 12:29 PM
How do you pull the trigger with the big space gloves on?

Rig your lever action like Lucas McCains, so you don't need to pull the trigger. They are still available. Click on "Own a Rifle"

http://www.riflemansrifle.com/

7x57
03-15-2009, 12:41 PM
if water can get in my rounds, air can get out ;)

Yep, they'll equalize pressure (which in space means losing all pressure, except for the vapor pressure of the volatiles in the powder). I recall a description of a test in a reloading manual (probably the .45-70 blackpowder in the Speer manual, but I don't recall) where they loaded the ammo several days before the test to make sure that all were at the same (atmospheric) internal pressure.

It would be sort of interesting to know if there is more leakage past the bullet or the primer.

7x57

Scott0san
03-15-2009, 12:51 PM
My local gun shop had one of these last year. It came with 10 rounds of ammo. little rockets that start slow but end up at around 2000fps. I am sure they would start a fire is shot anywhere near dry grass
A cool gun developed and made in Walnut creek or Danville. I cant rermember.


http://world.guns.ru/handguns/hg172-e.htm

dadoody
03-15-2009, 12:59 PM
I was thinking the recoil would instead racking the slide, would simply be transfered to the entire gun, and on to the person.. Oh yea, I would guess limp wrist would be really bad. But I didnt think the fast recoil impulse would not make a difference in a zero G environment. Then again, maybe you're right.

It would fire the bullet and load the next round, but if the person isn't attached to anything the person will float back also

56Chevy
03-15-2009, 5:30 PM
Rig your lever action like Lucas McCains, so you don't need to pull the trigger. They are still available. Click on "Own a Rifle"

http://www.riflemansrifle.com/
You've thought too much about this topic.:p

Thefeeder
03-15-2009, 5:40 PM
You have to understand that the lack of gravity and atmosphere does not equal the lack of inertia.

A stationary object will stay stationary until acted upon by an outside force.

The stationary object would be the gun, the hand holding the gun, the body that the hand is connected to. The only thing different that firing a gun on the ground is there is no gravity holding you to the floor, and the presence of atmosphere.

Imagine falling in an elevator. You are falling at a rate that causes you to be weightless. Would you still be able to fire the gun and have it operate as designed? YES. However when you pulled the trigger, the force would push your body slightly away from the direction of the bullets travel. There would still be more than enough resistance for the action to work properly and for the gun to cycle. The absence of air would only allow the bullet to travel for a longer distance without slowing due to air resistance.

+1 elementary physics folks...refer to Newtons laws of motion

wash
03-15-2009, 6:07 PM
OK, now someone has to try to bump fire an AK while parachuting in freefall.

NeoWeird
03-15-2009, 6:56 PM
Let me go back to what I was trying to refer to in my first post.

Since we're talking about someone going to space, I assumed (and if it's outside the rhetorical I'm sorry) that we were talking within the confines of space that we've been. Once you leave the Earth's atmosphere gravity does NOT stop working upon you. What happens is there is no longer air resistance to slow you down. You accelerate to the point that your free fall places you in the theoretical same elevation to the Earth's surface but in a different location along the orbit of travel. The result is a perpetual free fall. Gravity still exists, which is why things like meteors and crap like that are still pulled into Earth, or any other celestial body. You get simulated weightlessness because everything around you is traveling just as fast as you, and is free falling just as much as you, that any additional force added onto them will effect them as if they were weightless.

It's like driving in a car and you lob a tennis ball to another person in the front seat. Did the ball travel at the 5 mph you threw it at or the 80 mph ground speed when you factor in the fact that the car has already accelerated the ball to 75 mph? To you it seems like 5 mph, to someone on the ground it's 80 mph. This is why they say that a small object like a pebble in space, that is not moving or going the opposite direction or Astronaughts, would shoot right though them. It's not the pebble that is dangerous, it's the astronaughts speed who is traveling at about 18,000 MILES PER HOUR at orbit. This is why when astronaughts are in space they orbit the Earth several times a day.

Now we go over to the ammunition, which when properly loaded will be air tight and contain enough propelant and gases to burn consistantly enough to give proper ignition and fire the gun. Physics tells us the force on the bullet and gun will be the same as each other. In a handgun design that utilizes Brownings tipping barrel the brass and bullet will form an air tight seal and continue to be influenced by the expanding gases until a breach in the system is made (either by the action opening or the bullet exiting the barrel). The resistance of the barrel to the bullet and the case pushing against the breech face will cause the action to continue normally as it would on earth as in either case weight is not an determining factor. The firearm will fire fine and if anything it will OVER perform, so to speak. With that said, the first problem I forsee comes to play.

On Earth there is atmospheric pressure that gets compressed. This pressure may cause straight blowback guns to opperate FASTER than on Earth and they may open prematurely, or even at dangerous speeds that could cause the bolt to shoot out the back of the gun (assuming you're NOT in an enviorment controlled chamber, like on a space ship, but rather outside in a suit). In a tipping barrel design the second the system is opened, the lack of pressure compared to the VERY high pressure of the system would cause rapid decompression, though at that point there is probably enough enertia in place to fully open and opperate the firearm and the bullet will continue on it's course. In a gas system it's a combination of the both. The system may have less resistance and open too soon, like an AR with a weak or soft buffer spring, or it may only open partially and short stroke once the system opens and pressure stabilization occcures. Either way, it would not be some giant feat to get all three to work. An adjustment of springs is probably all that would be needed to get any of them to work properly.

The BIGGEST problem with firing a gun in space is not the physics behind it, but rather getting the primer to fire hot enough to ignite the powder consistantly in the sub-zero temperatures of space.

Turbinator
03-15-2009, 7:26 PM
I decided to Google it. Look at this thread of non-gunnies trying to figure out if a firearm would work in space (on the moon, to be exact):

http://community.discovery.com/eve/forums/a/tpc/f/1261917489/m/6191973899

Amazing how many people DON'T know how a firearm, or ammo, works.

Turby

ty423
03-15-2009, 7:36 PM
How do you pull the trigger with the big space gloves on?

Winter trigger guard... Magpul has it.

andrewj
03-15-2009, 7:40 PM
It would fire the bullet and load the next round, but if the person isn't attached to anything the person will float back also

Indeed. If you were doing a space walk (without a restraining cable) and fired a gun, the recoil would propel the you backward until someother force stopped or redirected you.

trinydex
03-15-2009, 7:41 PM
I was thinking the recoil would instead racking the slide, would simply be transfered to the entire gun, and on to the person.. Oh yea, I would guess limp wrist would be really bad. But I didnt think the fast recoil impulse would not make a difference in a zero G environment. Then again, maybe you're right.

you could easily do the momentum calculations and see how much the person moves relative to the gun. my guess is that all of the firearms will work. the lubrication is sort of an issue.

bohoki
03-15-2009, 7:41 PM
How do you pull the trigger with the big space gloves on?

bump stick

anybody who thinks there is enough air to oxidize diddly squat inside of a case is smoking something funny

14 psi to 0 psi is nothing to a properly seated bullet and with the wolf sealant on cases it shoud be fine from offgassing as if you are going to get a bunch of nitro dripping out of some bullseye

heck you could probably load and use a black powder muzzle loader if you use the pyrodex pellets

AaronHorrocks
03-15-2009, 7:44 PM
Maybe in outerspace you can use firearms as a form of propulsion.

It's already been thought of. But think bigger.... mini nukes being drobbed out of the back of a ship... you can be accellerated at great speeds. :thumbsup:

trinydex
03-15-2009, 7:45 PM
The most expensive one ever!

you could easily simulate the same situation by hanging someone upsidedown and telling them to shoot a glock.

NeoWeird
03-15-2009, 7:55 PM
The force applied to the gun (and you) would be the same as the force applied to the gun. So let's say it's a 9mm shooting a 124 grain bullet at 1,200 FPS. That means a 200 lbs man and a 5 lbs gun will be accelerated to 1/11,573 the speed of the bullet - 1.2 INCHES per second. Seeing as that's not even taken into consideration that you body can redirect momentum and absorb some momentum and I think it's safe to say unless you just dumping ammo on full auto then it's not really a danger issue to you leaving your current proximity.

Unless you think some Willie E. Coyote type business will happen and you'll pull the trigger, the bullet will stay motionless and you will fly back.

I decided to Google it. Look at this thread of non-gunnies trying to figure out if a firearm would work in space (on the moon, to be exact):

http://community.discovery.com/eve/forums/a/tpc/f/1261917489/m/6191973899

Amazing how many people DON'T know how a firearm, or ammo, works.

Turby

ow, ow, ow, OUCH!

That type of thinking hurts my brain. I mean, seriously, what do they think, the second the bullet leaves contact with the surface it loses all momentum that the moving surface had upon it? Ouch...I need a pain killer after reading only half of that.

Grumpyoldretiredcop
03-15-2009, 8:08 PM
One more complication no one seems to have thought about - the effect on the weapon itself from temperature extremes. IIRC, objects in shadow could become quite cold - theoretically, nearing absolute zero in interstellar space. Even in LEO (Low Earth Orbit), the temperature of a steel firearm in shadow could drop precipitously, which could affect the tempering of steel parts, such as barrels and slides, for example. Repeated exposure to unfiltered sunlight and cold certainly would cause embrittlement. Imagine firing that weapon in its supercooled state!

Note to self: Don't fire in the shade. :D

bohoki
03-15-2009, 9:42 PM
so the secret to space shooting is to make sure it doesnt get cool so shoot it every 10 minutes or so in the dark and if you fire in one direction and feel yourself drifing shoot exactly 180 degrees behind you

so if you touch of a full glock 18 mag would you be doing backflips?

7x57
03-15-2009, 10:19 PM
parachuting in freefall

Um... but....surely you realize...I mean, did you think that...look, if you...

Oh, never mind.

7x57

7x57
03-15-2009, 10:44 PM
Astronaughts


I'm quite enchanted by the thought of whatever an "astronaught" might be. An astronaut who is a "real zero," perhaps? :D

Sorry, couldn't resist.


Now we go over to the ammunition, which when properly loaded will be air tight


Nope. Ammo isn't really airtight, nor would it matter if it was.


and contain enough propelant and gases to burn consistantly enough to give proper ignition and fire the gun.
[QUOTE]

No gasses are needed. Gunpowders are monopropellants and need no separate oxidizer. The only gasses inside a cartridge is air, and it's just taking up space.

[QUOTE]
On Earth there is atmospheric pressure that gets compressed. This pressure may cause straight blowback guns to opperate FASTER than on Earth and they may open prematurely,


This should not be an issue at all. I can't imagine that air resistance is slowing down any slide or blowback bolt. It absolutely won't "shoot out the back of the gun." Even if your hypothesis were correct, you'd just get a tiny bit of extra frame battering, equivalent to shooting a slightly hotter load.


In a tipping barrel design the second the system is opened, the lack of pressure compared to the VERY high pressure of the system would cause rapid decompression,


I don't know what you're getting at here, but rapid decompression is what happens every time a round is fired in any gun. Fifteen PSI more or less on the outside is not going to make any difference at all when there is still a few thousand PSI of pressure when the bullet exits the barrel. And I don't know why you think recoil or gas-operated actions would be affected differently than blowback. All would be affected the same: negligibly.


The BIGGEST problem with firing a gun in space is not the physics behind it, but rather getting the primer to fire hot enough to ignite the powder consistantly in the sub-zero temperatures of space.

The heat capacity of gunpowder is small, this won't be a problem.

The chamber shattering in a gun which has equillibrated to, say, four degrees Kelvin might be a problem though. :eek:

But why do you assume the gun is cold? Space is a great insulator, and you'd have to be in deep shade to equilibrate to the 4K background radiation. If you leave it in sunlight (I assume earth orbit, obviously the answer is different out in the Oort cloud) for a long time, it's going to get hot. Mighty, mighty hot. Be interesting to know if it could start cooking off rounds if left out long enough.

But the most realistic case is that the gun is normally in a climate-controlled environment and only go out when the astronauts suit up for a job requiring arms (what that would be I leave as an exercise to the aspiring Science Fiction writer). In that case, it isn't going to have a lot of time to heat up and it *certainly* isn't going to have time to cool down before the oxygen runs out.

7x57

7x57
03-15-2009, 10:53 PM
I decided to Google it. Look at this thread of non-gunnies trying to figure out if a firearm would work in space (on the moon, to be exact):

http://community.discovery.com/eve/forums/a/tpc/f/1261917489/m/6191973899

Amazing how many people DON'T know how a firearm, or ammo, works.

Turby

That's some bad juju just to *read* that. Notice how the confidence of a poster in his answers is inversely proportional to his amount of knowledge?

I sort of liked this line:


only a freaken old musket wouldn't fire because there isn't a blasting cap.


So what *does* happen if you try to use a blasting cap to prime a cap & ball weapon? :eek:

Excuse me, a freaken old blasting cap. :D

7x57

7x57
03-15-2009, 10:58 PM
the temperature of a steel firearm in shadow could drop precipitously, which could affect the tempering of steel parts, such as barrels and slides, for example.


I don't know about altering the temper, but I suspect you'd shatter the chamber if the gun has really equilibrated in deep shade. I finally thought of that responding to another post, but hadn't gotten here yet to see that you'd already thought of it.


Note to self: Don't fire in the shade. :D

There's no problem firing in shade unless the gun has been there a long time; space is a great insulator. As long as you brought it into the shade with you, blaze away.

7x57

Decoligny
03-16-2009, 11:09 AM
How do you pull the trigger with the big space gloves on?

That's why you use the lever action rifle with the "Rifleman" setup. The really wide opening and the machine bolt that pushes against the trigger to fire every time you cycle a round.

Satex
03-16-2009, 11:18 AM
A firearm should operate just fine in space since smokeless power contains its own oxidizer. The operator would have to take the recoil into account. If the operator holds the firearms close to his center of mass and point the firearm away from it, he could use it as an effective propulsion system. The only concern I would have operating a firearm in space is thermal. On earth, the atmosphere takes heat away via convection. In space we don't have convection and we have sever gradients depending on field of view to the Sun or cold space. It is conceivable that a firearm could overheat faster than it would on Earth.

Army
03-16-2009, 2:08 PM
...and the plane will indeed take off from the moving runway.

wcnones
03-16-2009, 2:45 PM
Two important questions I want to know the answers to:

1. Is Kimber better than Glock in space?

2. If you tethered yourself to a bullet and then fired it in space, would you collapse into a wormhole when the bullet reaches the end or the tether because of the opposing forces now joining back together?

85FourEyedGT
03-16-2009, 5:36 PM
I think nasa should test it! strap 100 glocks onto a ship and fire them at the same time to get some propulsion goin ;)

gewgaw
03-16-2009, 6:35 PM
It is conceivable that a firearm could overheat faster than it would on Earth.

This is the best observation yet, in this awesome thread. If you kept shooting, wouldn't the chamber and barrel melt fairly quickly from the heat that has nowhere to go?

Gun barrels on earth heat up because air is a relatively good insulator... vacuum is the ultimate insulator. OK math whiz people, how long before my AR-10 barrel melts and... uh... what would happen in space if a barrel melted from the heat of repeated firing, anyway?

:confused:

Desert_Rat
03-16-2009, 8:12 PM
I think that the lube problem would not be due to it freezing like in arctic conditions,but more like it boiling off due to the lower pressure.By lowering the pressure you have lowered the boiling point.Like while pulling a vaccum on an A/C system in a tractor(I'm a tractor tech)You lower the atmospheric pressure inside the system and this causes any moisture/h2o vapor to boil and evaporate and be pulled out.
Just the opposite a pressureized radiator does not overheat/boil,due to the raised pressure caused by the radiator cap(and anti-freeze).
mind you I only have HS education and some vocational education.

Pugster
03-16-2009, 8:50 PM
Air convection helps somewhat to cool a gun but IIRC the ejection of the hot brass carries a lot more of the heat away.

Not really sure how a melting barrel would pan out in space with zero gravity. I would think that the barrel would start expanding a lot more from the chamber out to the opposite side.


This is the best observation yet, in this awesome thread. If you kept shooting, wouldn't the chamber and barrel melt fairly quickly from the heat that has nowhere to go?

Gun barrels on earth heat up because air is a relatively good insulator... vacuum is the ultimate insulator. OK math whiz people, how long before my AR-10 barrel melts and... uh... what would happen in space if a barrel melted from the heat of repeated firing, anyway?

:confused:

pepsi2451
03-16-2009, 9:07 PM
Shouldn't we have tried this when we went to the moon? I mean they brought a gold club, they could have brought a gun. They should have had them there in case of aliens anyway right? They should have dumped a few mags while they where up there.

Baron
03-17-2009, 8:30 AM
check this out...
http://www.russianspaceweb.com/almaz_ops2.html


OPS-2 (Salyut-3)

A two-day test mission of the Soyuz spacecraft, developed specifically for the Almaz program, preceded the launch of the OPS-2 station. The 7KT version of the Soyuz was launched without crew on May 27, 1974 and announced as Cosmos-656. (52)

A month later, after a night-long struggle on the launch pad with electrical problems in the interface between the station and its rocket, the OPS-2 space station, blasted off from a "left-hand" launch pad at Site 81 in Baikonur on June 25, 1974. It was announced as Salyut-3. (100) Official Soviet sources discolosed that the new station was equipped with an "electro-mechanical" attitude control system, or gyrodines; rotating solar arrays; an "improved" thermal control system, and that it featured separate areas for work and rest. (71) The first use of a water-recycling facilities, and of unmanned reentry capsules was also acknowledged. (2)

The post-Soviet sources (134) listed following payloads onboard OPS-2:

The Agat-1 photo-camera, with a focal length of 6,375 millimeters and a resolution better than 3 meters.
The OD-5 optical visor,
The POU panoramic device
A topographical camera
A star camera
The Volga infrared camera with a resolution 100 meters
Cosmonaut Pavel Popovich, who trained for the Almaz mission and later manned the station, recalled in an interview with the Novosti Kosmonavtiki magazine that the station carried 14 different cameras in all. (153)

The station was also equipped with a "self-defense" gun developed at a design bureau led by Nudelman. The weapon was installed in the front section of the station and in order to point it at the target crew had to change the attitude of the entire station. During ground test firing, the gun was able to split in half a metal container. At the same time, the firing caused considerable shaking of the station itself, therefore in-orbit tests of the weapon during manned operations were ruled out.




here's a bit more reading about the above link....
http://www.fourmilab.ch/documents/spaceguns/
As Professor Newton pointed out some years ago, if you fire a cannon in space, you're going to end up going in the opposite direction with some haste. While permitting one to avoid a “fight or flight” decision by simultaneously exercising both options, it would be disconcerting to discover that in the heat of combat you had accidentally deorbited your battle station. So, the station was equipped with orbital maneuvering engines which automatically fired when the cannon was blazing away to cancel its recoil thrust.





This too is kinda crazy...
http://www.jamesoberg.com/russiangun_tec.html
The Russian Gun At The International Space Station
James Oberg

From “Star-Crossed Orbits: Inside the US-Russian Space Alliance”, chapter 11


Russian participation means that there are guns on board the ISS, and the guns belong to the Russians. This is not quite as alarming as it sounds, and officially it’s no secret. However, I could never find any mention of this design feature on NASA web sites or mission press kits. Actually, it’s a safety feature, and not an unreasonable one.

American astronauts who trained for the 1995–1997 Mir visits, and later as part of the Soyuz spacecraft crews for the International Space Station, encountered a unique feature that cosmonauts need to master: target practice. They have to know how to load, aim, and fire the special survival gun that has been on board all Soyuz spacecraft throughout their 30-year history.

The triple-barreled gun can fire flares, shotgun shells, or rifle bullets, depending on how it's loaded. The gun and about 10 rounds for each barrel are carried in a triangle-shaped survival canister stowed next to the commander's couch. The gun's shoulder stock opens up into a machete for chopping firewood.

Familiarization with the gun usually takes place during survival training in the Black Sea, when the crews train to safely exit a spacecraft floating on the water (although a firing range at the cosmonaut center at Star City near Moscow is sometimes used for training). After floating around in the water for a day or two, the astronauts and cosmonauts take a few hours to fire several rounds from each chamber off the deck of the training ship.


"It was amazing how many wine, beer, and vodka bottles the crew of the ship could come up with for us to shoot at," astronaut Jim Voss told me. "It was very accurate," he continued. "We threw the bottles as far as possible, probably 20 or 30 meters, then shot them. It was trivial to hit the bottles with the shotgun shells, and relatively easy to hit them with the rifle bullets on the first shot."


"It is a wonderful gun," agreed Mir veteran Dave Wolf. "I found it to be well balanced, highly accurate, and convenient to use."


Mike Foale trained with the gun and found it to be pretty standard. “Other than firing flares, bird shot, and a hard slug from its three barrels, during sea and winter survival training, I can’t say it is very unique,” he told me. He added, as if in reassurance, “The Soyuz commander controls its use.”


Every Soyuz spacecraft carries such a gun, although none of these guns have ever been unpacked in flight. And they have never been needed, with the exception of an incident in 1965, when bears (or wolves—the story varies) chased two far-off-course cosmonauts. The guns are often presented to crew members as postflight souvenirs. Although several survival kit bags have shown up at space auctions, I’ve never seen any of the guns for sale.



I can't quite make it out in the pic, but this is a picture of the gun....
http://msnbcmedia4.msn.com/j/msnbc/Components/Photo_StoryLevel/080212/080212-space-gun-vlarge-2p.widec.jpg
http://www.msnbc.msn.com/id/23131359/