Confused about air pressure.

[Keith2324]

Hopefully someone can enlighten me on a few things. Let's say I have an FX Royale 500 and a Daystate MCT. Both have the 500cc aluminum bottle. The manufacturer's recommended pressure on the FX is 200 bar and the MCT is 230 bar. What is the main difference for the drop in pressure for the FX? Is it valving or the regulator? In addition, if you replace the bottle on either of the guns with a carbon fiber bottle, somehow your pressure can be increased to 250 bar. I'm just curious as to how this works.

Keith.

 

[dizzums]

im not entirely sure how criticsl a few pounds might be, but overfill a gun too much and it will 'lock out' .. the hammer wont overcome the valve lol ... most guns ive had shoot best a couple hundred under their max fill anyway .. all this assumes a factory tune though .. im sure with work and a rated bottle you can open its parameters up some

 

[JimNM]

The valve, hammer and spring should be dialed in to work at a specific pressure. Just because the bottle can be stuffed with higher pressure, the system is not designed to work at the higher pressure.

 

[nervoustrig]

It depends on whether you are dealing with a regulated or unregulated PCP.

If unregulated, the fill pressure is generally dictated as dizzums and Jim described…there is a pressure above which the hammer is unable to knock open the valve sufficiently. There’s too much pressure holding the valve closed so you get a valve lock situation (0 fps) or at least a partial lock (low fps).

If regulated, the fill pressure is generally dictated by the maximum safe working pressure of the reservoir.

Granted, you certainly have to observe the maximum safe working pressure in an unregulated PCP as well, but that will always be something higher than the pressure at which it works optimally. By that I mean the pressure at which you get the beginnings of a useful bell curve. (If that’s not the case, it means the tune needs to be adjusted so it does produce a useful bell curve at a safe pressure).

 

[Healthservices]

And if both are regulated by different regulators it could be the design of the regulator. one may not be designed to regulate the proper output pressure at higher input pressures.

 

[elh0102]

It depends on the variables mentioned. I have an FX Royale 400. It has the 220 bar max engraved on the receiver, a carryover from the previous aluminum bottle used. I contacted both FX and Huma, and both said I was okay using a 250 bar maximum with the carbon fiber bottle. Based on my experience with a couple of rifle makers, I believe the bottle rating is the most common limiting factor on pressure. My take is, the valves and other internals are usually going to okay at 250, but I would verify with the maker before going higher. I'm a little surprised at the 200 rating on the HW100. Seems that heavy steel cylinder should be good for something higher. But, it could be based on other parts, or just general conservatism. 

 

[Solo1]

I believe this is exactly why fx came out with the maverick. The regulators have trouble with the extreme pressure their expected to work at so you build 1 reg to withstand a big hit and 1 to be a little more accurate. Daystate commonly it seems puts 230 as a max pressure not because their bottle won’t take it but because the reg works more efficiently from 230 to set pressure. At least thats what i think

 

[nervoustrig]

Regarding the Maverick dual regulator concept, note input regulation and refresh rate are competing factors in a regulator design.

In other words, you can have it do a good job at holding a stable setpoint as the input pressure rises and falls if you don’t need it refresh quickly.

Or you can have it refresh quickly if you’re okay with the setpoint moving up and down a bit with the reservoir pressure.

I think that’s what FX was trying to achieve with 2 regulators--an arrangement that can do both.

Note dual regulators have been a thing in the paintball world for a long time. There, rapid fire rates and low setpoints (wide reservoir operating range) make it advantageous. For the Maverick, their press release says it’s designed with slug shooting in mind which means high energy -> high air consumption -> need fast refresh. Else follow up shots will be slow. That’s my interpretation from reading between the lines. 

 

[Glem.Chally]

If it says max 200 bar on the royale is a an unregulated model? Mine says 220bar on the reciever.

 

[Beezer]

My BSA Lonestar .25 is self regulated. At between 170 and 210 BAR it acts like a regulated rifle without all the extra complexity, weight and cost of a fully regulated rifle, much like a Daystate Hunstman that uses the Harper Slingshot valve. The BSA Lonestar also has a fabulous trigger, and since I shoot CZ firearms and have become a "trigger snob", I like my BSA Lonestar very much. The salesman at AoA that sold me my Lonestar also used the Lonestar as his personal rifle (that was 11 years ago), and AoA sold some very nice rifles that cost a lot more and have more snob appeal, like the Daystate Huntsman, which is still available new, in several versions. However, mine is the long barrelled Lonestar version, and most I have seen on the internet are the shorter barrelled version with a different version of stock as well. My rifle was only available for export at the time, so was never sold in the UK. My stock has the later supplied full length checkering on the forearm. BSA has never since sold a rifle as powerful as my Lonestar.

I do not see the loss of full regulation as a minus in my situation, since I go for higher power and the 10 shots that I receive in self regulation is enough for a hunting situation if not a target shooting situation. When talking to AoA about installing a Huma regulator in my Lonestar, I would get more shot counts but at a lower power level. The regulator would be set at a lower level than the 190 BAR that my rifle works best at. Also, the Huma regulator would take up internal air volume and my maximum shot count in regulation would probably not be increased in any significant amount, if at all.

One could fill a Huma regulated Lonestar to 250 BAR and set the regulator to around 190 BAR, but the power would not be increased and internal air volume would be lowered, and since I get 3/8" 5-shot groups at 50 yards as it is, no significant accuracy gains would be acheived as well, and any accuracy gains above that are really not noticeable in a windy field hunting situation in Montana. Just more weight to carry around at more expense and the additional risk of developing a regulator issue.

So when it comes to air pressure and power, for me at least, it comes down to hunting or target shooting. For a 12 FPE target rifle, better to go regulated at a lower pressure, for a 50 FPE hunting rifle where only a few good shots are needed, no need to go fully regulated as higher pressure tends to work better as the Daystate Huntsman and BSA Lonestar have proven. The downside of the BSA Lonestar is that it does not have variable power like some fully regulated rifles have. Heavy pellets penetrate 3/4" plywood and 2x4" pine studs. No good for varmint elimination in buildings as it will shoot through most wooden structures. I have a Sheridan .20 cal for the low pressure variable power duties.