Rail gun

[458mag]

http://www.foxnews.com/tech/2016/03/17/futuristic-military-railgun-bullets-could-travel-at-mach-6.html?intcmp=hpbt2 Would love to see the impact on target.

[Half Dog]

That is very impressive.

[perotter]

Something like 20-30 years ago when they thought that a material that would work as a super-conductor at normal temperatures was about to be found there were a few reports about rail guns that would be hand held. A much higher fps than what the article mentions. A line of sight weapon that fired a BB sized projectile would have enough range to be used against airplanes. Such an arm would replace the assault rifles, anti-tank arms and Stinger type arms.

But of course those super conductor material break troughs were the end about the end of it for now.

[NavyVet1959]

Technically, it's not a firearm, right? :)

Well, at least federally. I seem to remember some states even classifying BB-guns as "firearms".

[MaryB]

MN classifies them as firearms...

[NavyVet1959]

MN classifies them as firearms...

Yeah, I figured it was a "Yankee Thing"... :)

[Ballistics in Scotland]

Experimentation has been carried on for years on a former military airfield near my home in Scotland. I don't know any of the details, but it does suggest it is considered worth some trouble and investment.

It has interesting potential as a weapon, although I don't believe it has been made anywhere near practical yet. It requires a large power supply, and a sort of capacitor to be charged and deliver an enormous burst of power, much like your photo flash does with a small battery. I don't believe making it man-portable is a serious consideration any more.

As an artillery piece it should be extremely good at penetrating armour, in which extreme velocity has a disproportionate effect.(Hollow charge projectiles do it with liquefied aluminium or steel.) But other things are going to make heavy armour less significant on the battlefield than a couple of decades ago. It may provide less of a "signature" in heat and in disturbed dust and vegetation than conventional artillery, to air or satellite observation. It seems unlikely that it will be able to project anything like sophisticated electronic equipment (into space, say), since the g force on acceleration will be so extreme. (Even Jules Verne's cannon for sending his heroes around the moon would, on the basis of escape velocity and its length, have reduced them to a small and unpleasant puddle in the bottom of the shell.) I don't believe anybody would fancy pressing the button if it was to fire a nuclear weapon. It may eventually become cheaper to make than a large rifled gun, but so far the rapid erosion of the rails makes it impractical as a weapon.

[Rick Hodges]

Interesting since the US Navy is fielding an operational one on the new Zumwalt class destroyer.

[Wayne Smith]

Again, someone beat me to it. Yup, the USN is making it operational as we speak.

[Mk42gunner]

Even if they get the rail gun to work acceptably, I don't see the conventional gun with HE projectiles going completely away- there are too many jobs for naval gunfire that call for something other than solid shot.

I also don't see this becoming field artillery anytime soon due to the electrical power requirements.

Robert

[Rick Hodges]

My understanding is the rail gun will be replacing one of the 2 155mm guns on the Zumwalts. They are keeping the conventional canon. I can't see much use at all for a rail gun for shore bombardment.

[Wayne Smith]

Doesn't have to be limited to solid, but at those velocities even a solid shot hits with devistating authority.

[Ballistics in Scotland]

Interesting since the US Navy is fielding an operational one on the new Zumwalt class destroyer.

As of a month ago I believe they were considering fitting it to the third Zumwalt destroyer, which will (or should) become operational in 2018. That is a class curtailed from the 32 originally intended, and it would sidestep the sea testing of prototypes. The shipyard building the ship said they haven't been told. Presumably it would replace at least one of the two Advanced Gun System weapons, which can fire ten projectiles per minute with an accuracy far exceeding the First World War Paris gun, and not much less range. That is some way off deciding that the rail gun is a practical naval weapon.

[Ballistics in Scotland]

Even if they get the rail gun to work acceptably, I don't see the conventional gun with HE projectiles going completely away- there are too many jobs for naval gunfire that call for something other than solid shot.

I also don't see this becoming field artillery anytime soon due to the electrical power requirements.

Robert

They have been tested with a fairly small explosive charge, but I would suspect that their effectiveness would be limited by an inability to carry the same range of time and proximity fuses. The g force of acceleration would be far greater than with a conventional gun. I once saw a most heartening Discovery Channel in which a repro Civil War Parrot rifle very convincingly thrashed the Canadian Army's light field gun for 1000 yard accuracy. In real life, though, this would be offset many times over by the modern fusing and planned fragmentation.

[Mal Paso]

Something like 20-30 years ago when they thought that a material that would work as a super-conductor at normal temperatures was about to be found there were a few reports about rail guns that would be hand held. A much higher fps than what the article mentions. A line of sight weapon that fired a BB sized projectile would have enough range to be used against airplanes. Such an arm would replace the assault rifles, anti-tank arms and Stinger type arms.

But of course those super conductor material break troughs were the end about the end of it for now.

Smith and Wesson will have a concealed carry model in their 2220 lineup called "Grasshopper" ;)

[Blammer]

Smith and Wesson will have a concealed carry model in their 2220 lineup called "Grasshopper" ;)

with the typical S&W safety that automatically engages at random, just for your safety, don't you know...

[Garyshome]

A Wheel Railgun?

[Windwalker 45acp]

and this is just what they're willing to let us know about! Imagine all the cool things we never get to see....

[NavyVet1959]

A Wheel Railgun?

Maybe something operating like the Phalanx system of a railgun could be considered a "wheel" railgun... :)

https://upload.wikimedia.org/wikipedia/commons/thumb/0/0b/Phalanx_CIWS_test_fire_-_081107-N-5416W-003.jpg/450px-Phalanx_CIWS_test_fire_-_081107-N-5416W-003.jpg

[MUSTANG]

Claims of 100 mile range. Would be interesting to see some weights of projectiles fired and the ballistic coefficients for the projectiles.

On a pure "Line of Sight" analysis, they could become problematic due to curvature of earth affect. As an example: If a 64 inch tall person's eyes are at a height of 60 inches or 5 feet, they might be able to see at night, a flashlight laying on the ground at 1.23 the root of 5 = 2.75 miles. They would also be able to see another like standing person's headlamp twice that distance or at 5.5 miles distance, since each person would be able to see the midway tangent point.

Use against and airborne target would be much more viable, but that 100 Mile range without the ballistics data being available becomes more cloudy.

[NavyVet1959]

Claims of 100 mile range. Would be interesting to see some weights of projectiles fired and the ballistic coefficients for the projectiles.

On a pure "Line of Sight" analysis, they could become problematic due to curvature of earth affect. As an example: If a 64 inch tall person's eyes are at a height of 60 inches or 5 feet, they might be able to see at night, a flashlight laying on the ground at 1.23 the root of 5 = 2.75 miles. They would also be able to see another like standing person's headlamp twice that distance or at 5.5 miles distance, since each person would be able to see the midway tangent point.

Use against and airborne target would be much more viable, but that 100 Mile range without the ballistics data being available becomes more cloudy.

We already shoot over the horizon... Parabolic arc path...

[Ballistics in Scotland]

Claims of 100 mile range. Would be interesting to see some weights of projectiles fired and the ballistic coefficients for the projectiles.

On a pure "Line of Sight" analysis, they could become problematic due to curvature of earth affect. As an example: If a 64 inch tall person's eyes are at a height of 60 inches or 5 feet, they might be able to see at night, a flashlight laying on the ground at 1.23 the root of 5 = 2.75 miles. They would also be able to see another like standing person's headlamp twice that distance or at 5.5 miles distance, since each person would be able to see the midway tangent point.

Use against and airborne target would be much more viable, but that 100 Mile range without the ballistics data being available becomes more cloudy.

I think 100 miles is just something they hope for in the future. The figures you suggest are interesting but pretty academic, since there is likely to be some refractive effect on the line of sight so close to a curved surface. Most days I see a sandbank five miles away which dries to a height rather less than five feet. It seems to float above the horizon in all but really cold weather, and whether I stand on the seawall or with my feet wet makes no difference. But you can't refract a trajectory, so directly aimed fire is already of very dubious value for even conventional five-mile artillery. Clearly the rail gun must be an indirect fire weapon against terrestrial targets. The Advanced Gun System which the rail gun may replace on the Zumwalts, was originally a vertical gun, capable of firing only guided munitions, and I think that is intended in its current form.

I was once taught French by a delightful old lady, born with the century who used to come back from retirement for summer courses. She remembered the Paris Gun of 1918 very well, and remembered the general scorn of its ability to hit anything smaller than a city. I don't know if any attempt at pinpointing military or communications targets was made, but if so, it didn't work. It killed about 2/3 of a person per shell (not much over half of that if an unfortunate incident in one crowded church is eliminated), and for an amazing technical accomplishment, it was a pretty miserable success. Because of the thick shell wall required to withstand a fraction of the rail gun's acceleration, it fragmented very badly.

I think, therefore, any long-range use of rail guns will depend on guided munitions, with rocket assistance a possibility. (There is no firm dividing point between rocket assistance and the base-bleed munitions used to reduce range in conventional artillery.) If the G forces on launch permit the use of GPS guidance, it would be a great advantage. Even the 50 metre circular of error of the Advanced Gun System would have been good news to anyone in the trenches of the First World War, and while volume of fire with the AGS would surely make it successful against bridges, tunnel mouths, magazines etc., it is uncertain whether the rail gun will be able to fire as rapidly.

[Ballistics in Scotland]

We already shoot over the horizon... Parabolic arc path...

It is a mighty funny sort of parabola, rather more hockey-stick shaped under conventional atmospheric drag, with two different kinds of slightly ramshorn-shaped twists due to two kinds of drift, and another due to wind. When that trajectory is high enough, drag and wind drift vary at different heights along the shell's path... At such ranges many things matter which never mattered for anything else.

I imagine that the Paris gun involved some sort of mechanical computer, which was in use on battleships, and they may have been some way ahead on the improvements which were introduced by 1939. CS Forester the novelist says, very truthfully, that any foreign power would gladly pay to have a knowledgeable man spend a little time in the darkened room where the Royal Marines band sat around a glass table with dials, and that was only a light cruiser. That technology was kept on Ronald Reagan's de-mothballed battleships, because it couldn't be bettered. It probably can now, a little. But a missile self-guided to a point identified by GPS would surely transform its effectiveness.

[NavyVet1959]

It is a mighty funny sort of parabola, rather more hockey-stick shaped under conventional atmospheric drag, with two different kinds of slightly ramshorn-shaped twists due to two kinds of drift, and another due to wind. When that trajectory is high enough, drag and wind drift vary at different heights along the shell's path... At such ranges many things matter which never mattered for anything else.

Agreed, but I was stuck typing on a touchscreen device and couldn't be my usual verbose self. :)

[MaryB]

Homemade rail gun https://www.youtube.com/watch?v=KMT97bqaOdM

[Artful]

https://www.youtube.com/watch?v=N0D3WN-ep-A

[Artful]

https://www.youtube.com/watch?v=DD2dtAqJcJ4

[Ballistics in Scotland]

Homemade rail gun https://www.youtube.com/watch?v=KMT97bqaOdM

It's impressive. Of course it must be operating at a much lower velocity than the naval version. But on that level it has interesting possibilities.

I'd much prefer not to see people using them as anti-intruder devices. Car alarms go off by themselves fairly often, and they only shock a less vital part of the system. I once had the police break into my home, when a roof leak passed my apartment by and leaked into the bank below. I suppose they have a legitimate interest in finding out if I have died in my bath with the water running, and blasting them seems excessive.

It has the interesting characteristic, in the UK, of not being a firearm because it doesn't combine lethality with a barrel, and it isn't prohibited unless the missile is explosive or poisonous. It isn't a airgun (licence if over 12ft./lb.) and it isn't a crossbow (unlawful to shoot all wildlife except fish.)

[popper]

At 200 joules/grain of smokeless powder, that home made one is VERY inefficient. Yes, rail guns, laser guns work BUT - remember the cowboy shows where they NEVER reload after a couple 100 shots? As stated previously, energy source is the problem with either. Nuke generator would do the job. Ship board rail gun makes sense for AA, just 'bullets' required on board. Problem with laser AA gun is time on target required to do thermal damage. Either should be capable of high rate of angular change aiming (gun slew rate). Both require intercept aiming.

[AggieEE]

As part of Regan's star wars program they had an air borne laser using a chemical oxygen iodine laser COIL. The laser itself was about the size of a big block v8 and the power output was about the same, 10's of kW IIRC. It required a dwell time on target of about 5 to 10 secs. They had a complicated mirror system to compensate for the thermal bloom of the air getting hot. Interesting from an engineering standpoint.