Condor Air Rifle, Air rifle velocity
So I was looking at various air rifles, just our of curiosity, and came across this one.
22 caliber, claims a max velocity of 1250 fps, and about 30 shots on one tank of air at full power before the velocity starts to significantly drop.
Well I mentioned this rifle to my dad, and his BS alarm went off.
The speed of sound at sea level is about 1,100 feet per second. This means the individual air molecules are moving at that speed right? and as such an air rifle cannot propel a pellet faster than the speed of sound.
According to physics for ideal gases, pressure has no effect on the speed of sound through a gas, but the root of temperature is related to the speed of sound, and increasing the temperature of a gas by 4x raises the speed of sound 2x, and that is why firearms have no problem propelling bullets faster than the speed of sound in the outside air.
Then I found this scientific article: www3.imperial.ac.uk/portal/pls/portallive/docs/1/4651920.PDF
Knowing at high pressure/density ideal gas laws break down, this measured the speed of sound at various pressures and temperatures. One of the graphs shows that at very high pressure the speed of sound begins to increase. I opened the graph in pain, took the 300 K line (about 27 C/ 81 F), and extended the line, and yielded a linear approximation of a 90 ft/sec increase in the speed of sound at 3,000 PSI. If air has a similar increase in the speed of sound as methane, this would mean these rifles are shooting at the very limit of the possible velocity.
Are current air rifle velocities limited by how hight one can raise the speed of sound in the pressurized tank?
If so you could probably measure a 10% difference in velocity shooting from 0 Fahrenheit weather to 115 Fahrenheit weather.
Can the Condor really shoot supersonic pellets? Are the pellets limited by the speed of sound in the compressed gas(ie doesn't matter how long your barrel is or how much compressed gas you have)?
If this is the limiting factor, is the difference in velocity measurable when shooting at different temperatures?
22 caliber, claims a max velocity of 1250 fps, and about 30 shots on one tank of air at full power before the velocity starts to significantly drop.
Well I mentioned this rifle to my dad, and his BS alarm went off.
The speed of sound at sea level is about 1,100 feet per second. This means the individual air molecules are moving at that speed right? and as such an air rifle cannot propel a pellet faster than the speed of sound.
According to physics for ideal gases, pressure has no effect on the speed of sound through a gas, but the root of temperature is related to the speed of sound, and increasing the temperature of a gas by 4x raises the speed of sound 2x, and that is why firearms have no problem propelling bullets faster than the speed of sound in the outside air.
Then I found this scientific article: www3.imperial.ac.uk/portal/pls/portallive/docs/1/4651920.PDF
Knowing at high pressure/density ideal gas laws break down, this measured the speed of sound at various pressures and temperatures. One of the graphs shows that at very high pressure the speed of sound begins to increase. I opened the graph in pain, took the 300 K line (about 27 C/ 81 F), and extended the line, and yielded a linear approximation of a 90 ft/sec increase in the speed of sound at 3,000 PSI. If air has a similar increase in the speed of sound as methane, this would mean these rifles are shooting at the very limit of the possible velocity.
Are current air rifle velocities limited by how hight one can raise the speed of sound in the pressurized tank?
If so you could probably measure a 10% difference in velocity shooting from 0 Fahrenheit weather to 115 Fahrenheit weather.
Can the Condor really shoot supersonic pellets? Are the pellets limited by the speed of sound in the compressed gas(ie doesn't matter how long your barrel is or how much compressed gas you have)?
If this is the limiting factor, is the difference in velocity measurable when shooting at different temperatures?
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I don't like it, it's black and it looks mean.
Guns are supposed to have wood stocks with ducks and deer engraved on them. And be made in the USA, by Union Labor. And fit in the gun-rack on my Chevy.0 -
well that particular air rifle is made in the US, and it might fit your gun rack.
feel free to cover it with balsa wood and carve your ducks and deer on it if your really desire such.
Use a can of spray paint for the rest of the rifle.0 -
I'm too lazy to do the math, but I do believe that an airgun can reasonably be expected to fire a projectile at supersonic velocities. If, on trigger-pull, the loss of pressure was adiabatic (god how I hated that word when I was taking physics), then you'd be limited to the speed of sound. On the other hand, loss of pressure on trigger-pull is far from adiabatic, so I believe that yes, because there is a temperature differential involved, you can exceed the speed of sound.
Consider those air-guns powered by CO2 cartridges. As a kid we used to get those cartridges and whack the nipple-end against something sharp--just to see the thing go flying through the air (fortunately nobody was hurt during this game!). When we found the cartridge a few seconds later it was invariably cold enough to have frost on it...on an 80-degree day.
I've heard (and I believe) that when the conditions are just right, if you're standing some distance from a canon, it is possible to hear the report of the canon before you hear the order to fire it. Actually, I got that out of my the physics textbook that I so hated--except for that detail.0 -
Actually, I believe the expansion is adiabatic, anytime something expands really quickly, its adiabatic, its simply expands too fast to absorb any appreciable heat from its surroundings.
Assume there is no temperature differential, and this pre-charged Pneumatic rifle (ie filled with air before hand, not CO2) has its tank come into thermal equilibrium (as you compress gas, it gets hot, so when you are first filling the tank it will get hot).
It is correct that the pellet cannot exceed the speed of sound of the gas inside the barrel and chamber, right?
I think I answered it myself when I found that article showing the speed of sound does actually increase slightly at really high pressure(but temperature and molecular weight of the gas have a far greater effect)0 -
Doesnt gamo claim they go supersonic with the lightweight lead free PBA pellets and their hunter extreme rifle? 0 -
quote:Originally posted by CA sucks
Actually, I believe the expansion is adiabatic, anytime something expands really quickly, its adiabatic, its simply expands too fast to absorb any appreciable heat from its surroundings.
Assume there is no temperature differential, and this pre-charged Pneumatic rifle (ie filled with air before hand, not CO2) has its tank come into thermal equilibrium (as you compress gas, it gets hot, so when you are first filling the tank it will get hot).
It is correct that the pellet cannot exceed the speed of sound of the gas inside the barrel and chamber, right?
I think I answered it myself when I found that article showing the speed of sound does actually increase slightly at really high pressure(but temperature and molecular weight of the gas have a far greater effect)
k. Maybe somebody who really knows can answer this.
1. You're right: adiabatic means no transfer of heat (I confirmed that on Wikipedia), but....
2. If a gas under very high pressure suddenly comes to be under very low pressure adiabatically....then that extra energy has to go somewhere, right? Like into the supersonic velocity of the projectile!
Jeez, I really hope somebody who knows what they're talking about chimes in because I'm sure I don't have it right, but I'm also sure that an airgun can produce a supersonic projectile.0 -
Oh what a beauty! what is the cost? I now an shooting .177 at 1200 fpc.Can knock a tree rat out of a tree top at thirty yds.
quote:Originally posted by CA sucks
So I was looking at various air rifles, just our of curiosity, and came across this one.
22 caliber, claims a max velocity of 1250 fps, and about 30 shots on one tank of air at full power before the velocity starts to significantly drop.
Well I mentioned this rifle to my dad, and his BS alarm went off.
The speed of sound at sea level is about 1,100 feet per second. This means the individual air molecules are moving at that speed right? and as such an air rifle cannot propel a pellet faster than the speed of sound.
According to physics for ideal gases, pressure has no effect on the speed of sound through a gas, but the root of temperature is related to the speed of sound, and increasing the temperature of a gas by 4x raises the speed of sound 2x, and that is why firearms have no problem propelling bullets faster than the speed of sound in the outside air.
Then I found this scientific article: www3.imperial.ac.uk/portal/pls/portallive/docs/1/4651920.PDF
Knowing at high pressure/density ideal gas laws break down, this measured the speed of sound at various pressures and temperatures. One of the graphs shows that at very high pressure the speed of sound begins to increase. I opened the graph in pain, took the 300 K line (about 27 C/ 81 F), and extended the line, and yielded a linear approximation of a 90 ft/sec increase in the speed of sound at 3,000 PSI. If air has a similar increase in the speed of sound as methane, this would mean these rifles are shooting at the very limit of the possible velocity.
Are current air rifle velocities limited by how hight one can raise the speed of sound in the pressurized tank?
If so you could probably measure a 10% difference in velocity shooting from 0 Fahrenheit weather to 115 Fahrenheit weather.
Can the Condor really shoot supersonic pellets? Are the pellets limited by the speed of sound in the compressed gas(ie doesn't matter how long your barrel is or how much compressed gas you have)?
If this is the limiting factor, is the difference in velocity measurable when shooting at different temperatures?0 -
Some meen airguns out there, try this
http://www.pyramydair.com/cgi-bin/model.pl?model_id=961
or a
http://www.airgunsbbguns.com/career_707_shinsung_air_rifle_pcp_s/99.htm
these beasties do 50-80 flb,in .25 cal & 9mm. [:0]0 -
Don't know the velocity, but kinda like the looks of this'n. 0 -
Not get off topic, but I have always wondered how Nitrogen would work as opposed to air. for the temperature change. 0 -
Best damb air gun I ever shot! that set up in the pic will run you about a grand with a hand pump.I can cut a thread at 60 yrds,
adjustable power range and crisp trigger!With the 24 inch barrel
it sounds like a 22, but I got mine down to a mouse fart! If you want email me and
I will get yoy the info!0
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