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Discussion Starter · #1 ·
A little known type of gun once dominated the high velocity gun world. It was called the "light gas gun" (LGG). Outwardly resembling a large, conventional gun or small cannon, the LGG used a novel means of attaining higher velocities than usually possible with gunpowder.

Normally, powder guns are limited to muzzle velocities of about 5300 feet per second. This is because gunpowder can only burn so fast and cannot push a bullet any faster. At some point adding more powder only acts like a hevier bullet, as the powder must push its own weight too.

The LGG has a chamber divided into two separate sections. The rear section contained the gunpowder. The forward section was filled with a low density gas such as helium. Dividing the forward and rear chamber sections was a movable piston. In front of the piston was the helium. In front of the helium, holding it in, was a thin disk. In front of the thick disk was the bullet.

When the gun was fired, the powder burned, building up pressure which pushed the piston forward. As the piston moved forward it compressed the helium. At some point the helium was under so much pressure that it would rupture the disk and push the bullet down the barrel. Since the helium was so light, most of the energy could go to pushing the bullet. Because the pressure of the helium at disk rupture was so great, the bullet achieved a phenomenal muzzle velocity, perhaps as much as 14,000-17,000 feet per second.
 

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Bet it's hell on barrels! What sort of projectiles are used? I would think air friction would become a significant factor at those speeds.

Any work been done on using this method contained within a moderately sized self contained replaceable "cartridge"? When you say "large" conventional gun, how big is that exactly?

Wonder what something like that would do to a squirrel? :dgrin:
 

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that was pretty funny

about the squirrel, there RICH Z.


but what i cyhperd was the begingings of the RAIL GUN,

ENERGY WEAPONS ARE THE WAVE!

israel, is cuttin' edge! :cool:

just read YOUR BOOK!, we all know how it ends


i would like to know what country worked on this 'gas booster?'

GUN



THANKS.
 

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Discussion Starter · #4 ·
Rich Z said:
Bet it's hell on barrels! What sort of projectiles are used? I would think air friction would become a significant factor at those speeds.
They were mostly used for research guns. They were fired at targets to study the terminal ballistics. The projectiles for such were custom made and frequently were saboted. But you are right that the air friction would be extremely high.

Rich Z said:
Any work been done on using this method contained within a moderately sized self contained replaceable "cartridge"? When you say "large" conventional gun, how big is that exactly?
Commonly guns of this type are a dozen feet long.

Rich Z said:
Wonder what something like that would do to a squirrel? :dgrin:
Picture a bug hitting a windshield on the highway.
 

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After I read your thread I Googled light gas guns.WOW!The links I found were re.guns w/barrel lenghts around 20m.Fit that in your pocket!I realize that they were test barrels but I have one question?
Why not have a second gas cartridge behind the gun powder? to cool the bore?I mean,from the breech,have a gas(cooling),powder,gas(accelerating)projectile lineup.
I was just reading an article about the .220Swift this morning that talked(again)about how max loads had a "blowtorch"effect on the barrel & that obviously was w/speeds a small percentage of what a lgg is capable of.It seems to me that if you could have a cooling gas delayed behind the propellant gas(es)then,maybe,you could both extend the bores life & speed up a following shot.The few articles I started to read seemed like proof of concept like tests.Kinda like"hey!kool toy!i wonder what would happen if ..."& the "if" never came.
Or am I all wet?
 

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Discussion Starter · #6 ·
41mag said:
After I read your thread I Googled light gas guns.WOW!The links I found were re.guns w/barrel lenghts around 20m.Fit that in your pocket!
The barrel length chosen depends on the volume of the chamber and the caliber.

41mag said:
I realize that they were test barrels but I have one question?
Why not have a second gas cartridge behind the gun powder? to cool the bore?I mean,from the breech,have a gas(cooling),powder,gas(accelerating)projectile lineup.
For me the biggest timetaker when using research guns is mounting and positioning the target. After the shot you are busy examining the data and the test target.

Target work is tedious. The violent impact of the projectile inevitably damages backstops, which you must repair. I've frequently had nearby circuitry in the target chamber pulverized by flying pieces of target, so that has to be rebuilt for the next shot. The bore is cool long before the next shot. You're typically doing one to six shots a day.

I was just reading an article about the .220Swift this morning that talked(again)about how max loads had a "blowtorch"effect on the barrel & that obviously was w/speeds a small percentage of what a lgg is capable of.It seems to me that if you could have a cooling gas delayed behind the propellant gas(es)then,maybe,you could both extend the bores life & speed up a following shot.The few articles I started to read seemed like proof of concept like tests.Kinda like"hey!kool toy!i wonder what would happen if ..."& the "if" never came.
Or am I all wet?
What you have suggested is a really good idea. Since LGG chambers require filling with helium, their rate of fire is too slow to overheat during research use.
 

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Discussion Starter · #7 ·
41mag said:
After I read your thread I Googled light gas guns.WOW!The links I found were re.guns w/barrel lenghts around 20m.Fit that in your pocket!
I am familiar with one LGG that is described as 29m long with a bore of 5mm and a barrel of 1m.
 
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