Maximum Pressure?

One thing that seems to have been a so far unstoppable trend in airguns has been the ever increasing maximum pressure used. Antique pneumatics operated at pressures under 1000 psi and while CO2 might exceed that on a hot day it was mostly under 1000 psi too. When more modern PCP's came out their maximum pressure was largely capped by the pressure of scuba tanks and the work of hand pumping. Because scuba tanks typically only held 3000 psi when full and the early guns were unregulated, this resulted in a typical gun being fully charged at 2700 psi or less. Of course most were rated for 3000, but their sweet spot was typically lower than that.

With the advent of carbon fiber tanks, affordable compressors and regulated guns it seems the new standard is 4500 psi. Sure some guns still do fine with less, but when you've got a regulator and your compressor can give you 4500 psi every time more pressure means more power and more shots per fill.

Things don't really stop at 4500 psi though. Hubens have a max fill of 5000 psi and the new AEA air cartridges actually fire at 5000 psi and AEA also has a new big bore that's designed for 6000 psi.

This makes for some interesting possibilities and potential hazards. What happens when we start working with 10,000 psi? At that point airgun performance will actually be on par with many centerfire powder burners. I can't help but think they will also be inherently more hazardous than powder burners due to the reservoirs and valves always being under pressure. There will also be the obvious hazard of people overfilling their older guns. For decades now I've heard fear mongering about coming regulation of airguns. 20 years ago it was because of powerful big bores. These days it's because of full auto. What seems far more likely to me however is if we have a rash of deaths and injuries due to 10,000 psi cylinders and overfills that the various regulatory agencies will step in and regulate us from a consumer safety standpoint.

For those of you with an engineering background, what's holding us back from a physics standpoint? Is there a maximum practical pressure that we will reach simply due to the molecular properties of air or the physical complications involved with compressing it?

Edit: After typing this all out I discovered that there is a very similar recent thread already on the forum. I'm going to leave this up as I probably brought up some stuff that isn't present there, but here is the link to it and I'm definitely following it as well.
 
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Apart from extra shot count I don't see any advantage on higher reservoir pressure. The volume increase is in anyway not linear with the pressure increase.

Negatives as I see it is much more stress on metal components, O-rings and especially the regulator. Also the weight increase for the stronger reservoir is not something I want.

I have no desire to have such high pressure vessels.
 
Yeah I think Im good at the current 4350psi. That is plenty enough energy to demand my respect for the equipment touching my face. I will gladly make the trade off balance between fps and shot count limited at those pressures. And honestly I dont even fill my 300Bar setups to 300Bar anyway to make things easier on all the parts. But I do applaud the industry drive to meet consumer demand with more creative engineering.
 
Apart from extra shot count I don't see any advantage on higher reservoir pressure. The volume increase is in anyway not linear with the pressure increase.

Negatives as I see it is much more stress on metal components, O-rings and especially the regulator. Also the weight increase for the stronger reservoir is not something I want.

I have no desire to have such high pressure vessels.
How about power or noise? More pressure equals more power and a shorter higher pressure blast of air can be much quieter.
 
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These tanks/airtube is test to withstand 3 times what it's rated for. You can have a 10,000 psi tank but are you sure your valve will open? Lol. Many guns will valve lock at 3500-4000 psi. So good luck opening your valve with 10,000psi. Many guns these days have regs, so the valve will never see what the tank pressure is.
There are valve designs that can work with higher pressures though, balanced valves for example, and even with a 10,000 psi fill the valve might "only" be dealing with 7,000 psi.
 
There are valve designs that can work with higher pressures though, balanced valves for example, and even with a 10,000 psi fill the valve might "only" be dealing with 7,000 psi.

I just mentioned in another thread. My PV has only 349 lbs of holding force at 32,000 psi...typical of a .30/.357 caliber...

I personally welcome 7000-8000 psi fills and 4500 regulator set points, a proper pilot valve will laugh in the face of such pressure while making gobs of power.

-Matt
 
Did you see the word "mostly"?
And, the mention of higher reg pressure for a 300bar fill is for the existing rifles made for 300bar fill.

So, what is false about that?

Anything to be right these days eh?
The higher pressure mostly involve the reservoir and not the regulated plenum pressure. You can have a higher reg pressure with a 300bar fill as well but nowhere near the 300bar for the plenum.

Check the bolded underlined part...

NO WHERE NEAR 300 BAR FOR PLENUM EH? EH? YOU SAY ?

Lol...carry on mate.

-Matt
 
No, you cannot stand to be opposed in your ideas and again, I say what you say, you are the one trying to pull every string so you can to be right and then came up with the tethering idea. Tethering a 300 bar gun with a 300 bar SCBA tank ??? Unless you get a higher pressure vessel at cost, bulk and weight, after the first shot it is not 300 bar anymore. How many people are doing tethering anyway? How many people are hunting with the gun tethered? You see, you are pulling every string to be right. BE PRACTICAL.

And, how many guns have 300 bar regulators in it? How long will current regulators last when set to that pressure?
 
We're talking "AIR" guns while they do have limitations even tho some are pushing what that definition and limits are :unsure:
As a tuner that has played with many valve types, plenum sizes & calibers, the amount of power that can be extracted from sub 2k pressures is nothing short of amazing.
Cothrin found this out as did JSAR and FX, having Uragan follow there R&D in Balance valve tech and SKOUT similar with a spool valve. While theoretically a balanced or spool valve does not make power than a conventional valve at equal pressure/s, the miens in which most balanced valves re-profile in a way the release of the plenum pressure at a VERY rapid rate due to there ease of opening, yet by design ( Not FX ) take the released pressure within the valve throat using it to force the valve closed again. This Spike we call a HIGH AMPLITUDE pulse that launches a projectile very hard. Due to generally shorter valve dwell ( Open duration ) the noise leaving muzzle is far less and total air consumtion can be tuned to be far less.
* Because these type valves Do Not require heavy hammers or heavy springs, guns using them cock easier, have less mechanical recoil/vibration and trigger mechanics are less straigned. This valve tech caters to HIGH OUTPUT uses and not needed or really wanted unless so.

So for subject of this thread .... super high pressures for the average air gunner ( Average a loose term ) simply is not nessessary to make the power that our target, sport or hunting air guns require ... IMO 250 bar or less is more that enough !!

JMO ...
 
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