Scotaty:
I sometimes wonder why people ask questions when they already know the answers...Your question triggered the response of FX customer service and I spent quite some time trying to explain something to somebody who I believed asked a fair question in search for a fair answer...
You seem to know and understand high/low BAR pressures and understand the many alternatives on how to accomodate the Belleville washers in order to bring pretty much the same force, so unless you think that in a 11 washer stack it makes much difference to have the last 3 washers set like in your gun (() vs. )() I now don't understand your initial concern.
I own two FX Impacts MKII Power Plenums, a .22 and a .30 and I bough another in .177 which was unfortunately destroyed, all three came with 10 washer amp regs. I've also fixed 4 amp regulators (creeping)...All of these 4 were from people who were blaming FX and complaining about a $2000 gun creeping publicly when in reality it was a user's fault issue....Again, all of these amp regulators also came 10 washers and I only added a flat washer to one that needed more stack height and added an extra washer to another that was going to be set at 160 BAR ...So 10 or 11 or (() or )(( is not going to make noticeable difference...But you already knew that.
You are absolutely right in everything you said. My question is why are these variations? Are they designed and tested? Which one should I follow when I rebuild these regulators?
Scotaty:
The original design of the FX Impact did not contemplate the power/velocities that the current market demands...A MK1 originally was able to shoot competively (power/velocities) but after the last 2-3 years the velocity/power curve went exponential and this is why we have seen many iterations of the same gun...The market is changing rapidly towards more precise guns that can shoot at very high velocities/power...FX changed its regulator's piston to a longer one in order to get higher pressures (MKII) but then there were other guns shooting faster at the same pressures...FX reacted accordingly and introduced the larger Power Plenum at the end of last year.
Regulators are not tabu, they are simple valves that shut off with the force of a coil spring or Belleville washers, the later are more efficient (space/size vs. force) than coil springs and this is why they are the industry's prefefrence. If you assemble the washer stack (11 washers) like this: (()()()()() or like this: )()()()()() the difference in pressure will almost be negligible, the higher end will probably go 5-7 extra BAR and the lower end will stay the same or go slightly higher...Does it really matter if one regulator goes from 80 to 150 BAR and the other goes from 85 to 155-157? (rough estimate)...I really don't think so, adjust two identical HUMA high pressure regs and you will find anywhere from 3-6% discrepancies in the adjustability range.
Manufacturing companies are in constant R&D changing and trying new settings, systems, sub-systems and designs and if for example the second washer array above in combination with x.y.z changes/new components provided the best efficiency/power/precision, from there on the washers will be arranged in that manner...I have probably helped 10-14 friends shooting the Steyr LG-110 guns, I own 2 of those purchased 5-6 years apart...All I can tell you is that over the years their regulators have remained the very same design, but the washer configurations (number of washers/flat washers/force/and washer accomodation order) have changed at least 3-4 times...Same gun, same power levels and the only differences if any were different barrels...
What you found in your gun (reversed washer) is NORMAL for a dynamic company such as FX....And if it were a mistake, it will affect zero...So why pay attention to it or try to find the exact motive for the switch?
Can you turn around that last washer?...Of course you can!...Should you turn it around?, well, if the gun is working as intended, then why switch it?....I can assure you that you will get the same pressure you currently have and that you will not notice any difference in performance or precision...I machined several Titanium and Brass pistons for this FX amp regulator and the only difference other than the durability of brass and Titanium over synthetic is that given that the synthetic piston is lighter, the recuperation time in the original unmodified regulator is faster...Does it affect the shooter to use a brass or a titanium piston? Of course not, any of those materials will make the regulator recuperate faster than the anyone can shoot...You are talking a few milliseconds.
Our guns have evolved much in technology, but some shooters complicate the technological advances by looking for ghosts and things that don't exist...I know very few people that after messing around with their guns are honest enough to say: "I screw up the gun, it is my fault and not the manufacturer's" ...But then I constantly read shooters saying: "FX regulators creep", "FX regulators are not good for a $2,000 gun", etc...The truth of the matter is that ANY regulator will creep if you don't know what you are doing and mess it up...Regulators are not designed for setting them up-down-up-mid point, etc...Regulators should be set from low to high and should be left alone!...If you need to re-set it to a much lower pressure, the regulator will most likely creep and you will have to rebuild it (specially the set screw back pressure seal).
I don't know of any company that produces 100% perfection, guns are machines and machines are succeptible to fail regarding price, but I can assure you that 90-95% of the issues are ignorance or stupidity on the shooter's side. I have been shooting air guns, rimfire and shotguns internationally at very high levels since 1967 and in more than 50 years and hundreds of guns, I have never ever had a high end gun that came defective or with major issues...I dissassemble each and every gun up to the last pin/screw and put them back together...In the precess I learn how they work and improve or modify whatever is needed to suit my needs...But the difference is that I KNOW WHAT I AM DOING and I don't look for ghosts.
In conclusion: Get your gun, shoot it 2-3-5,000 pellets, learn it thoroughly while it settles down and then consider making changes to how you received it from the factory...The factory knows better than most shooters...Before making your changes STUDY what needs to be done and how it would affect the rest of the sub-systems, and don't forget to take notes/photos so you can reverse what you did.
As simple as that! Take care and good shooting,
AZ
