Faster Than a Speeding Bullet

[NAC4EV]

A First Look at America's Super-gun

In conventional guns, a bullet loses velocity from the moment the gunpowder ignites and sends it flying. The rail gun projectile instead gains speed as it travels the length of a 32-foot barrel, exiting the muzzle at 4,500 miles an hour, or more than a mile a second. It has a range of 125 miles.

 

[Jaskalas]

Yes, rail guns are real and soon to be deployed in a decade or two.
Combined with laser weapons, we'll dominate everything above water with near invincible forces.

 

[ElFenix]

In conventional guns, a bullet loses velocity from the moment the gunpowder ignites and sends it flying.

this is incorrect. longer barrels give the propellant a longer time to work against the bullet, increasing muzzle velocity. this lengthy railgun basically does the same thing but uses electromagnetics to impart velocity to the projectile rather than a chemical deflagration.

 

[MongGrel]

this is incorrect. longer barrels give the propellant a longer time to work against the bullet, increasing muzzle velocity. this lengthy railgun basically does the same thing but uses electromagnetics to impart velocity to the projectile rather than a chemical deflagration.

Pretty much this for starters, is why rifles are much more accurate at long range.

I'll just leave it at that, I do not want to get into a physics war if he doesn't know these things to begin with.

 

[Moonbeam]

Pretty much this for starters, is why rifles are much more accurate at long range.

I'll just leave it at that, I do not want to get into a physics war if he doesn't know these things to begin with.

Everything depends on what he means by sends it flying, if that means from the moment velocity is imparted or the moment it leaves the barrel.

 

[NAC4EV]

Apparently U.S. military engineers don't know jackshit

 

[Printer Bandit]

what would happen if you stood in front of it?

 

[MongGrel]

Everything depends on what he means by sends it flying, if that means from the moment velocity is imparted or the moment it leaves the barrel.

No it's not ...

 

[Jaskalas]

what would happen if you stood in front of it?

A big, messy, bug splat.

 

[NAC4EV]

what would happen if you stood in front of it?

You should give it a try.
Let us know how it works out.

 

[Newbian]

what would happen if you stood in front of it?

My guess is nothing good.

 

[blankslate]

this is incorrect. longer barrels give the propellant a longer time to work against the bullet, increasing muzzle velocity. this lengthy railgun basically does the same thing but uses electromagnetics to impart velocity to the projectile rather than a chemical deflagration.

Apparently U.S. military engineers don't know jackshit

How do we know that an engineer wrote the article....

because the fact is if you have two mostly identical firearms firing the same calber.

Such as a normal sized .45 acp and a concealed carry version of a normal sized .45 with a shorter barrel the version with the longer barrel will get generally higher velocities from the same bullet.
http://blog.cheaperthandirt.com/short-barrel-performance-45-acp-barrel-length/

The author in question made a mistake and was probably not an engineer....

________________

 

[WHAMPOM]

So seventy years later we repeat what the Nazi's did using secondary propellant charges to increase velocity in their super gun? Where is my plasma rifle?

 

[Ns1]

holy s that's amazing.

 

[JSt0rm]

maximize efficiency at killing brown skinned goat herders. What we need are terminators marching forth spreading freedom to all corners of the earth.

 

[UglyCasanova]

this is incorrect. longer barrels give the propellant a longer time to work against the bullet, increasing muzzle velocity. this lengthy railgun basically does the same thing but uses electromagnetics to impart velocity to the projectile rather than a chemical deflagration.

To an extent, but there is dismissing returns on the force of the propellant the longer the barrel to the point that it peters out on something really long. This is why the Nazis added additional charges along the length of their super gun.

Link

That's my understanding of it anyways, but I'm not an engineer. I think I saw a documentary that explained it that way.

 

[Moonbeam]

Quote:





Originally Posted by Moonbeam


Everything depends on what he means by sends it flying, if that means from the moment velocity is imparted or the moment it leaves the barrel.




No it's not ...

What isn't? If I say everything depends on something the denial of that would be no it doesn't, not no its not, so, first off, I don't know what you are saying, and secondly, if I said it, it has to be right. Everything depends on how we define let fly. A bullet accelerates down the barrel of a gun and begins to lose velocity after it leaves the barrel. That means that if let fly begins with the explosion of the powder the statement was wrong but if it means from the time it leaves the barrel it is correct. That's just the way it is. Nobody makes a gun so long that the bullet falls out at the end of the barrel.

 

[DrPizza]

What isn't? If I say everything depends on something the denial of that would be no it doesn't, not no its not, so, first off, I don't know what you are saying, and secondly, if I said it, it has to be right. Everything depends on how we define let fly. A bullet accelerates down the barrel of a gun and begins to lose velocity after it leaves the barrel. That means that if let fly begins with the explosion of the powder the statement was wrong but if it means from the time it leaves the barrel it is correct. That's just the way it is. Nobody makes a gun so long that the bullet falls out at the end of the barrel.

What about the other half of the sentence?

loses velocity from the moment the gunpowder ignites

No, at the moment the gunpowder ignites, it accelerates until the end of the barrel. Unless you want to argue that it means both things happen - in which case the sentence is still wrong - it should read, "from the moment the bullet leaves the barrel of the gun." Which, let's not forget, is in the context of a comparison to a projectile that accelerates down the entire barrel. Clearly, the author's understanding is that the "explosion" of the gunpowder gives the bullet all of its velocity in that instant, after which it starts slowing down. Were one to argue that by "and" - it means both things happen - the ignition of the gunpowder AND it reaches the end of the barrel (which again, makes no sense in the context of the comparison - "hey, this one does this, but the other one doesn't; it does this too" - it would be like saying, "I experience warm temperatures in January from the moment I turn the key in the ignition of my car and drive 1000 miles from NY to Florida."

 

[theeedude]

Your tax dollars at work. Really, big gun battleships is what the Navy has been missing all these years?

“I can’t conceive of a future where we would replicate Cold War forces in Europe,” said Deputy Secretary of Defense Robert Work, one of the weapon’s chief boosters. “But I could conceive of a set of railguns that would be inexpensive but would have enormous deterrent value. They would have value against airplanes, missiles, tanks, almost anything.”

Maginot line too? Are these people serious?

 

[Jaskalas]

Your tax dollars at work. Really, big gun battleships is what the Navy has been missing all these years?

The rail gun shoots football sized projectiles and does the damage of a missile at a fraction of the cost. Combined with lasers you're talking about a conventional military force that stands unopposed. A war with those weapons means opposing militaries can't even shoot back.

And you want us to drop our R&D?
You want us to lose our conventional advantage?

 

[Orignal Earl]

Yes, rail guns are real and soon to be deployed in a decade or two.
Combined with laser weapons, we'll dominate everything above water with near invincible forces.

Full-scale models have been built and fired, including a 90 mm (3.5 in) bore, 9 MJ kinetic energy gun developed by the US DARPA. Rail and insulator wear problems still need to be solved before railguns can start to replace conventional weapons. Probably the oldest consistently successful system was built by the UK's Defence Research Agency at Dundrennan Range in Kirkcudbright, Scotland. This system was established in 1993 and has been operated for over 10 years. Using its associated flight range for internal, intermediate, external and terminal ballistics, it achieved several mass and velocity records.[citation needed]

The Yugoslavian Military Technology Institute developed, within a project named EDO-0, a railgun with 7 kJ kinetic energy, in 1985. In 1987 a successor was created, project EDO-1, that used projectile with a mass of 0.7 kg (1.5 lb) and achieved speeds of 3,000 m/s (9,800 ft/s), and with a mass of 1.1 kg (2.4 lb) reached speeds of 2,400 m/s (7,900 ft/s). It used a track length of 0.7 m (2.3 ft). According to those working on it, with other modifications it was able to achieve a speed of 4,500 m/s (14,800 ft/s). The aim was to achieve projectile speed of 7,000 m/s (23,000 ft/s). At the time, it was considered a military secret.[citation needed]

China is now one of the major players in electromagnetic launchers; in 2012 it hosted the 16th International Symposium on Electromagnetic Launch Technology (EML 2012) at Beijing.[39] Satellite imagery in late 2010 suggested that tests were being conducted at an armor and artillery range near Baotou, in the Inner Mongolia Autonomous Region

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

 

[MongGrel]

What about the other half of the sentence? No, at the moment the gunpowder ignites, it accelerates until the end of the barrel. Unless you want to argue that it means both things happen - in which case the sentence is still wrong - it should read, "from the moment the bullet leaves the barrel of the gun." Which, let's not forget, is in the context of a comparison to a projectile that accelerates down the entire barrel. Clearly, the author's understanding is that the "explosion" of the gunpowder gives the bullet all of its velocity in that instant, after which it starts slowing down. Were one to argue that by "and" - it means both things happen - the ignition of the gunpowder AND it reaches the end of the barrel (which again, makes no sense in the context of the comparison - "hey, this one does this, but the other one doesn't; it does this too" - it would be like saying, "I experience warm temperatures in January from the moment I turn the key in the ignition of my car and drive 1000 miles from NY to Florida."

There is a reason pistol rounds use faster burning powder, instead of rifle rounds using slightly slower burning powder for gas expansion acceleration in the longer barrel also of course.

My point to begin was is he stated the bullet reaches max speed when the bullet leaves the casing I guess, not when it leaves the barrel.

Anyway...

 

[Darwin333]

Your tax dollars at work. Really, big gun battleships is what the Navy has been missing all these years?

Maginot line too? Are these people serious?

No, much smaller ships with big ass guns that have like 5 times the range of old huge ass battleship guns and a ton more power, accuracy and ammo.

 

[Moonbeam]

What about the other half of the sentence? No, at the moment the gunpowder ignites, it accelerates until the end of the barrel. Unless you want to argue that it means both things happen - in which case the sentence is still wrong - it should read, "from the moment the bullet leaves the barrel of the gun." Which, let's not forget, is in the context of a comparison to a projectile that accelerates down the entire barrel. Clearly, the author's understanding is that the "explosion" of the gunpowder gives the bullet all of its velocity in that instant, after which it starts slowing down. Were one to argue that by "and" - it means both things happen - the ignition of the gunpowder AND it reaches the end of the barrel (which again, makes no sense in the context of the comparison - "hey, this one does this, but the other one doesn't; it does this too" - it would be like saying, "I experience warm temperatures in January from the moment I turn the key in the ignition of my car and drive 1000 miles from NY to Florida."

What did the author mean by let fly? When is a bullet flying? If the article writer meant that the bullet flies from the moment it leaves the barrel the statement was correct, but if the author thought a bullet flies the moment the gun powder ignites then the statement is wrong. This is so because a bullet accelerates from the moment the explosion that propels it occurs all the way down the gun barrel and after leaving the barrel begins to slow down. The correctness or inaccuracy of the author's statement depends therefore on what the person who wrote visualized as 'flies'. The usual visualization of flight in most people's minds, I would submit, means independent movement through the air. One could reasonably, I suppose, describe a bullet traveling down a barrel, a flight. It was the ambiguity of the language I felt, that made the statement correct in one case and inaccurate in another, depending. So when something is right or wrong depending of factors unknown, one can't say with certainty that the statement is surely right or wrong. I hope that's clear because I'm not going to bother with this again.

 

[MongGrel]

What part of "a bullet loses velocity from the moment the gunpowder ignites" was vague ?

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