best rifle for the moon

Ftom14cat

New member
My brother and I were having an argument and we were hoping the internet could help us reach a reasonable answer. What is the best rifle for the moon and why?
 

zxcvbob

New member
Be more specific. You're on the earth and are trying to shoot the moon with a rifle? Or you want the best rifle to shoot on the moon? Or you *are* the moon and want to know what rifle to get?
__________________
"I'll have whatever he's drinking"
 

drail

Moderator
Believe it or not NASA actually selected the Remington Nylon 66 to be carried to the moon. It was later decided not to be included.:eek:
 

wogpotter

New member
I'm going with the inevitable.
Either a rail gun (mass driver) or a "Phased plasma rifle in the 40-watt range!":D

In all seriousness a .38 Spl revolver firing lubed cast lead bullets would be a reasonable compromise between recoil under lower gravity conditions & minimum chance of malfunctioning. Look up "Vacuum welding" a big problem with moving parts in vacuum & low gravity!:eek:
 

horseman308

New member
Given that space is a vacuum, and therefore without oxygen, how would any firearm successfully discharge (oxygen being necessary for combustion)?
 

Jim Watson

New member
Since no combustion is involved, the lack of oxygen does not matter.

I will say it again, gunpowder does not burn.
Smokeless powder is made out of nitrocellulose, some with nitroglycerine added. These are unstable chemical compounds and when hit by the primer flash, decompose into hot gases without the need of an external oxidant. The term is deflagration.

The only burning involved is when those hot gases hit the air and things like carbon monoxide ignite, causing muzzle flash. That won't happen on the moon.

No doubt felt recoil will be greater in 1/6 G, but the mass of your pressure suit will soak a lot of that up.

Robert A. Heinlein got by with Garands (Rocket Ship Gallileo).
You would want vacuum rated lubricants for any weapon.
 

kraigwy

New member
Since no combustion is involved, the lack of oxygen does not matter.

I will say it again, gunpowder does not burn.

Gunpowder, like any other high explosive, does in fact burn. How fast it burns is what makes it "high" explosive vs. "low" explosive.

Black powder is considered a low explosive because it burns rather slow. Smokeless powder is considered a high explosive because it burns quite a bit faster.

What makes is work in a firearm, is controlling the burn rate. If you have a high explosive, and just add fire, it burns slower. If you add concussion with the fire, then it burns much faster (some where a long the lines of 27,000 fps.)

To test this, lay out a pile of smokeless powder, add a match and watch it flair. Lay out another pile of smokeless powder, add a blasting cap, and it goes high order (explodes).

As to low explosive, such as black powder. You don't change the burning rate that much (notice the "that much", it does change a bit). You add a pile of black powder to a match, it flairs, much faster then the smokeless powder, kind of goes "poof". You add a blasting cap to the black powder if goes "poof" but looks like an explosion because you get a bigger 'poof" simply because you are scattering the black powder with the blast of the blasting cap.

Where you can get "what looks" like an explosion with black powder is if when you don't pack it. As in not seating the bullet on the charge, leaving air space between the charge of powder and projectile. You have to look at the pressure curve. Black powder appears to burn faster when loose, it builds its pressure curve "right now", then that pressure or gas hitting the projectile cause it to be retarded, or hit Resistance. In stead of a steady burn as in smokeless powder which will push the bullet out the barrel, the BP hits the bullet and whats to keep going fast, looking for the path of least resistance which could burst the barrel.

Smokeless powder builds up its pressure slower, starting from zero working its way out the barrel, if that pressure hits resistance (the bullet) it doesn't care, its still building up and will start pushing slowly, increasing until you get the velocity of the bullet you desire. To see this, read above about the difference when adding a match to black powder compaired to smokeless powder. Black powder appears to burn faster. It does at first.

The over all pressure is going to be higher with smokeless power then with black powder, its when that pressure is reach that counts.

Another way to look at it as to burning rate is to understand smokeless powder is made with nitrocellulose (gun cotton) or nitroglycerine or both. We know that different powders have different burning rates. This is accomplished with the size of the powder or the shape (tube vs flake). Some are coated to control the burning rate and to make it moisture proof.

As to having to have oxygen to burn, gun powder creates its own. As in black powder the oxygen comes from the saltpeter.

Sorry to muddy up the post. I know its a GUN forum and not a Bomb forum, but I didn't know how else to explain it with out interjectiong some EOD lingo.



As to shooting on the moon, that's a non issue with me, too far to drive and they don't let you smoke when you fly any more.
 
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MLeake

New member
Felt recoil should not be greater at all, as the masses of the charge, projectile, and weapon remain the same. In fact, the mass of the shooter would be greater than normal (space suit added); this might actually reduce felt recoil.

The ability of the recoil to move the shooter would go up somewhat, as friction with the surface would be less (mass isn't reduced, but gravity holding mass against the surface's coefficient of friction is reduced), and a force that would not overcome the gravity of Earth might overcome the gravity of the moon - but the recoil would not feel different to the shooter, he would just potentially get displaced more, although the initial acceleration would feel the same as it would on Earth; the velocity imparted might just continue longer than it would have on Earth.

This would be more of a problem in free-fall. Again, the F=M*A formula means felt recoil would really be no different, but now nothing would provide friction/resistance to opposite direction movement by the shooter. Recoil would feel the same as on Earth, but an unanchored shooter would continue moving until he came into contact with something that would stop him. (Or actuated a jet-pack, etc.)
 
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natman

New member
Gunpowder burns. Very quickly.
It doesn't need external oxygen because it brings its own chemically bonded as part of itself.
 

Glenn E. Meyer

New member
When you get there, do some ballistic tests on blocks of green cheese and post them on MoonTube.

Currently, the Russians carry some combo shorty rifle in their capsules. I think some of our early capsules had a SW Model 59 or similar semi.

If you do get the moon and see aliens - surrender because you are screwed and we are. Any civilization that can cross interstellar space isn't going to be cowed by fanboy stopping power! Resistance is futile.
 

brickeyee

New member
I'd say a .22 so you don't fly back 50 feet every time you pull the trigger.

Physics fail.

Your mass has not changed, just your weight from reduced griavity.
Gunpowder, like any other high explosive, does in fact burn.

No, neither smokeless powder not explosives burn in the conventional sense of using oxygen.

They break down rapidly into hot gases that THEN may oxidize (burn).

Nitrocellulose is actually under-oxidized.
It does not contain enough oxygen to bring all the gasses generated to a stable state.
Flash suppressors are chemical added to smokeless powder to provide oxygen when they break down to allow the reactions to reach stable compounds reducing the reaction with atmospheric oxygen that produces muzzle flash.

High order explosives break down and very high velocities, and can generate shock waves in solid material that can cause fracturing of the material.
Det cord is made of PETN (Pentaerythritol tetranitrate) in a hollow tube, and breaks down at 7,000 to 8,000 meters/second (~23,000 to ~26,000 feet/second).

There are also delay elements available to sequence a series of explosions.
 
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FrankenMauser

New member
Kraigwy said:
Gunpowder, like any other high explosive, does in fact burn. How fast it burns is what makes it "high" explosive vs. "low" explosive.

Kraig. You know just as well as I, that smokeless powder is not a high explosive, and is not classified as a high explosive. Don't confuse people. ;)


And, as others have said-
Smokeless powder does detonate (explode). It deflagrates (burns).
 

kraigwy

New member
Kraig. You know just as well as I, that smokeless powder is not a high explosive, and is not classified as a high explosive


Explain to me how nitrocellulose or nitroglycerine are not explosives

Classification is based on use. High vs. low explosive is determined by burning rate.

I don't want to go into "explosive and bomb making" here but as an example. Black powder is not a bomb. Black powder in a pipe is a bomb.

Smokeless powder in a rifle/pistol case is a propellant , you cap it its a a high explosive.

To dispose of Dynamite, you burn it. It doesn't (normally) explode, you cap it it does.

As to confusing people, people are confused, one only needs to read the paper about injuries and property damage each year do to making "home made" fireworks to see that education in this subject is important.
 
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BitterTait

New member
There's a lot of things to take into consideration. Lubricants evaporating in the vacuum and becoming a gummy or even solid mess. Temperature of 107 C in the sun, -150 C in the shade. Do primers/powder spontaneously detonate at that temperature? More or less all of the heat transfer will be radiant, so the sudden thermal shock wouldn't be too bad but still metals might lose a portion of their temper after a day in the lunar sun.

There's also vacuum welding, so small parts (pressed together from thermal expansion) may lock up. This would be worse with well fitted guns, more surface area in contact between the parts.

I can't say if a gas-powered semiauto would function in vacuum, I see no reason off hand for it not to, but if moving air out of the way acted as part of the buffering for the bolt then there may be some unwanted battering.

Moon dust is also a concern. It's small, it tends to stick to things via electrostatic attraction, and it's severely abrasive.

There's also the concern of how it will fit on a space-suited man. The bubble helmet makes conventional rifle sights nigh-impossible to use. There's minimal atmosphere so a laser sight would have much greater range then they would on the earth. The gloves means that any weapon would have to be redesigned to fit and trigger likewise modified for the sausage-fingered gloves.

Can't suggest a gun specific gun for the moon. Part of me says AK-47, but if a kalashankov functions flawlessly on the moon it'll just encourage the AK fans, and if it fails that would just create an equal and opposite reaction from the AR-15 side of the net.
 

divil

New member
A Glock 7 is obviously the winner.

  1. it is made from space-aged Moon-plastic
  2. it already weighs nothing (less than nothing in the case of the compact models)
  3. it will have no trouble getting through the metal detectors at the KSC

;)
 
I would suggest something chambered in a megamagnum, in order to insure a quick, clean kill. There is nothing more dangerous than a wounded orbital body rampaging that close to your home planet, looking for the jerk what shot it. I'll get back to you once I've found the proper manufacturer / caliber combo. Gonna take some fancy Googling.
 

brickeyee

New member
Black powder is not a bomb.

A sufficiently large quantity of black powder does not need ANY confinement to detonate.

Just a big enough pile on the ground.

Yo u can dump all the smokeless powder you want into an open pile, all it does is deflagrate. No detonation.

if it is on ANY type of enclosure (even a building) it may create enough gas fast enough to break out walls, windows, or a roof.

It will not create a shock wave (one of the defining things for a detonation).

Smokes can make a lousy pipe bomb, but it is more of a pressure vessel failure than a detonation breaking up the entire pipe like you can obtain with black powder.
 
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