Martian Firearms?

BigBore44 said:

I just want to know if you will be required to file for a permit for interstellar travel.

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Well, you’ll definitely need your vaccine passport...

Jim Watson said:

Yes, but it is still not a mixture, it is one or two chemical compounds you cannot separate into fuel and oxidizer.

Inorganic oxidizers are inefficient, black powder is 75% potassium nitrate, ANFO blasting agent is 94% ammonium nitrate.

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Sure, but you might be taking "mixture" to literal as I was speaking more general. None the less, neither black powder nor modern smokeless powder needs the presence of external oxygen in any form to function correctly. Firearms work in a hard vacuum or under water, so they will no doubt work on the surface of Mars in that particular atmosphere.

So we established the oxygen issue for the combustion, but what about recoil in blow back operated system.

Since we're going there....
Why do you even need it, if your name is a killing word?

What is there to shoot at? Second rock from the right?

Well, the crew of Rocket Ship Galileo took M1s to the Moon and shot Nazis.
Bound to be some bad actor on Mars.

Someone told me hearing protection is not required and no need to pick you trash yet.

You would need a pressurized suit and with a suit comes gloves. Is the trigger guard going to be big enough to get your pressurized gloved finger on the trigger?? asking for a friend!

If I shoot a Martian who is attacking me, is it still self defense? I mean, technically intruding on his planet, so is he protected by castle law?

The comments here (with a few exceptions) must surely be the stupidest I have ever read in this forum.

I was thinking there must be red deer to hunt up there.

Mars has 1% of the atmosphere of Earth. Lookup every single company that has come up with firearms/actions that shoot underwater, their problem magnified significantly. Shooting underwater is a fraction of the issue with flying a helicopter on another planet. The calculation differences taken into account of air density and composition between Earth and Mars are the stuff long chalkboards were made for.

My grandmother-in-law was in Houston control for Apollo 11-15(AFAIK, maybe more). I wish I knew the things she did on a slide rule compared to what everyone else does on computers and high end calculators.

The most amazing thing is that Even with the counter-rotating blades at some wickedly fast RPM (any blade hairline fractures?), that machine could create enough lift with such very thin air.

But guns work quite well up there, as demonstrated one hundred and sixteen (or so) years ago.
We know that tremendously huge cannons on Mars fired their giant projectiles to Earth in 1905, and their Fighting Machines using Death Rays and Black Smoke destroyed our cities . The cannon's fire on Mars was seen with our telescopes.

HG Well's classic story might be my favorite sci-fi adventure ever written (plus his "the Time Machine"). He rode a bicycle all Over the London area while creating his story's plot.

herrwalther- I finally noticed your comments.
Your grandmother-in-law and the other technicians/engineers were amazing people.
And how they shutdown enough electrical components on Apollo 13 to reduce oxygen consumption and keep those guys alive was so creative and innovative. It would have been ultra difficult even using computers.

Here the theory tested on mythbusters. I knew I saw this somewhere.

czhen said:

So we established the oxygen issue for the combustion, but what about recoil in blow back operated system.

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Recoil-operated systems (and gas-operated, for that matter) would work exactly the same as they work on Earth. Recoil is generated when the expanding propellant gases shove the bullet and themselves out of the chamber, down the barrel, and out the muzzle, while exerting equal rearward force on the case and breechface. On Earth, the 14.7 psi in front of the bullet is dwarfed by the 35,000-60,000 psi behind it.

The biggest differences would be the effects of extreme cold (already covered upthread) on lubrication and ammo, and that the trajectory would be vastly flatter—partly from the reduced gravity (38% of Earth’s) and partly from the bullet experiencing so much less drag in flight.

Some great science fiction referenced in this thread!

But, you're all thinking of the wrong sort of firearms.

This is what is wanted.



https://en.m.wikipedia.org/wiki/Gyrojet

Well suited to low gravity situations.

Aiming while wearing a pressure helmet is still problematic though. Some of you science Johnnies should work on this.

I think your most interesting and intriguing question is #3. The answers to #1 are now known and just require a ballstics calculator that will accept the extreme inputs. The answers to #2 just require the proper chemistry to provide ignition and burning in a Martian atmosphere. But #3? I wonder!! Hearing damage is produced by the extreme sound pressure levels and rapidity of change of the sound produced by detonation. At the Martian atmospheric pressure level the sound produced by the firearm would have a correspondingly low sound pressure level, wouldn't it? So my guess is, though I can't support it by data or calculations, is that even if you weren't wearing a helmet: NO, a suppressor wouldn't be required, because the level of the sound produced would be so low. And of course, if you're wearing a helmet, the question is moot anyway.

Gyrojets didn't work out, sorry. Although Larry Niven used them in some stories.

Did anyone post the Mars semi?

https://en.wikipedia.org/wiki/Mars_Automatic_Pistol

Demonstration of Gyrojet at
gyrojet video

BigBore44 said:

I just want to know if you will be required to file for a permit for interstellar travel.

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Not if you have your vaccination card.

GEM said:

Although Larry Niven used them in some stories.

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"Ringworld" books, if memory serves?

GEM said:

Did anyone post the Mars semi?

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Good one!!

Water, space, and Mars are very different physical areas to test.

Underwater you have a relatively dense liquid material acting as a bore obstruction which will greatly resist bullet motion. You have less usable oxygen for chemical reaction as well.

In space you have no bore obstruction whatsoever to slow down the projectile. You still have no usable oxygen to help with the shot.

On Mars you have a very thin atmosphere unlike space and unlike earth. It seems reasonable to say that it would function most similarly to earth or space since there is minimal material in the bore, it is gaseous, and there is gravity as well perhaps the gun will work much like on earth but with external ballistics being less affected by gravitational pull and wind resistance.

I think the Niven story was in a series of stories he wrote about an agent who worked for the UN that was part of his universe but not directly Ringworld.

GEM said:

I think the Niven story was in a series of stories he wrote about an agent who worked for the UN that was part of his universe but not directly Ringworld.

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Gil Hamilton - an agent of ARM!!

A corrollary question to #1 is: if you shoot a terrestrial rifle on the surface of Mars, will the bullet go into orbit? I've been googling for an answer for 15 minutes and all I come up with are complex mathematical formulas. I've got stuff to do!! You guys are keeping me from getting anything done today!!