FX Fx impact m4, why did they got rid of 1st reg?

Not saying their regs are trash. All regs will need service at some point. Is what it is. The fx are probably the most challenging and difficult ones to do on the market. There are two Oring’s in the process that will test your patience. Hence why you don’t want two. Most regs are straight forward and don’t have buried tiny orings you can’t hardly see.
I agree they are hard to get to, the trick is not to damage them. I owned one of the original Impacts .25 (gen1) when AOA sold FX and I never changed a single Oring in 4 years and countless pellets. I didnt mess with it much (tuning) the first couple years as it shot the .25gr JSBs lights out. Eventually I tuned it for the 34s around 910fps before Power Plenums were a thing. I sold it a while later and tryed other guns. The thing I like most about the power plenum is the low reg settings and great shot count. I own the M3 now .22 and so far so good for me.
 
Totally agree with this. Those south African boys never talk in their videos about poi shift or reg creeps or leaks, on their guns at all. They will only show the best groups and all the hits at long range to get normal folks with little knowledge thinking if they get the impact they will have the same result. Then found out they get problems with their impacts lmao.

I didn't know fx reg are trash. I think their guns 2k means it's like top of the line with little problems. If they do put trash reg in their guns, I would see a problem dealing with 2 trash reg needing maintenance. I guess that's why they have huma regs for the impact.
On my previous M2 I went from FX reg to Huma and back to FX reg. I don't understand why HUMA made the adjustment screw out of the softest metal with the shallowest of surfaces but it wasn't good.
 
  • Like
Reactions: coastal drifter
The older AMP regulators do not respond as fast or reset as fast as the new model AMP regulators.

As such, when you pull the trigger on a 30 cal M3 with a 700 mm barrel you are shoving, at a minimum, 31.92 cc's of air down the barrel at 850 to 950 fps. 31.92 cc's is 44.33% of the 720 plenum volume.

With two fast responding regulators, the plenum pressure control regulator will open, lowering the supply line pressure which opens the step down regulator which will increase supply line pressure lowering the differential pressure across the plenum pressure control regulator causing it to throttle close which in turn raises the supply line pressure causing the step down regulator to throttle close and this oscillation will continue with the regulators fighting each other until the plenum refills to the set pressure or we crank off another shot and make it worse.

When you run two pressure reducing regulators in series it is best to reduce the response of one to reduce the oscillations.

Apparently wth the old regulators one couldn't handle the load fast enough so two slower regulators were needed in series. Slow enough not to fight each other.

It will be interesting to see the performance of two fast responding AMP regulators in series. My bet is the plenum will fill to a bit higher pressure between shots.
 
  • Like
Reactions: josh9465
Totally agree with this. Those south African boys never talk in their videos about poi shift or reg creeps or leaks, on their guns at all. They will only show the best groups and all the hits at long range to get normal folks with little knowledge thinking if they get the impact they will have the same result. Then found out they get problems with their impacts lmao.

I didn't know fx reg are trash. I think their guns 2k means it's like top of the line with little problems. If they do put trash reg in their guns, I would see a problem dealing with 2 trash reg needing maintenance. I guess that's why they have huma regs for the impact.
I've had my m3 since nov of 2021 and it's never leaked or never had not even .1 of a bar of loss or creep. I have digial guages in every location. That's been my experience so far.
 
  • Like
Reactions: coastal drifter
I've had my m3 since nov of 2021 and it's never leaked or never had not even .1 of a bar of loss or creep. I have digial guages in every location. That's been my experience so far.
one thing I do have to say. Them removing the first reg was stupid. I run 300bar bottles only. it states on the gun not to exceed 250 bar. well that means either I now have to purchase some 250 bar bottles, or I have to spend more money to put a regulator on the gun, if it's possible on the m4, like the M3. I think this was a poop move by FX honestly.
 
They had 2 regs before because 1 regulator couldnt handle the preasure and now the new regulator is made out of brass so it can handle the preasure
This is only true if you’re using a maximum pressure of 250bar, if you want to run a 300Bar system you have to re-install the 1st reg as the now only 2nd regulator can’t deal with 300Bar.
 
one thing I do have to say. Them removing the first reg was stupid. I run 300bar bottles only. it states on the gun not to exceed 250 bar. well that means either I now have to purchase some 250 bar bottles, or I have to spend more money to put a regulator on the gun, if it's possible on the m4, like the M3. I think this was a poop move by FX honestly.
Why would you need to buy more bottles. You just fill the 300 Bar bottle you own to 250. Am I missing something ?

But yeah you’re correct to run a 300Bar system you do need to install the 1st regulator & manometer, but they do just simply screw in, it’s basically a 5 minute job. I recommend the Huma regulator it’s a little bigger and makes the bottle stick out about 20mm more but it’s much more reliable and made with better components 👍💪👍
 
I’m not having any trouble, I think the OP is. I’m not buying one because my M3’s are dialed. But if a M4 fell in my lap, after a couple hours of new gun disassembly and prep, I would know after one shooting session if I was ordering a first reg and gauge for it. For what I like to see across a full fill to refill range and what I expect out of a slug gun at both extremes, it may or it may not. I hopefully will never know.
Well said sir. I like your outlook on things. The M4 frankly doesn’t do anything for me with that bright new copper color. Looks more like a paintball gun to me than an air rifle. I love my M3, with 700cc 300 bar bottle. I do actually watch a ton of YouTube and I have not yet seen any of the Utah Airguns guys, or South African folks using a 300 bar tank on the M4s. In addition to the 300 bar bottle which is a big deal I do in general think that while yes it may make things more complicated it will save wear and tear on the gun having two regs vs one. I know in competition they would take them off and I would say of course. Most of those “pros” are getting these guns for free and will get the next one that comes out in six months for free too. They don’t care about wear and tear. My biggest point here would again be paintball guns. I used to shoot 2,000 rounds in a few hours playing paintball. Every worth while pb gun has two regs on board.
 
  • Like
Reactions: balver
Why would you need to buy more bottles. You just fill the 300 Bar bottle you own to 250. Am I missing something ?

But yeah you’re correct to run a 300Bar system you do need to install the 1st regulator & manometer, but they do just simply screw in, it’s basically a 5 minute job. I recommend the Huma regulator it’s a little bigger and makes the bottle stick out about 20mm more but it’s much more reliable and made with better components 👍💪👍
This was said prior to me owning an M4 and trying to do research on it. I own two of them now and it does support 300br bottle with just that one reg. It's absolutly perfect with no creep with it set at 100 bar and awesome.
 
  • Like
Reactions: balver
This was said prior to me owning an M4 and trying to do research on it. I own two of them now and it does support 300br bottle with just that one reg. It's absolutly perfect with no creep with it set at 100 bar and awesome.
Ahh that’s interesting 🧐 I contacted FX about mine & connecting a 300Bar bottle & they told me I had to install the first reg. Those liars lol 😂 thanks for the info 👍👍
 
you could test it. I'm not sure but I think the M3's 22's come with 85 or 90 bar reg. set from the factory. I don't know for sure because I've never purchased a new 177 or 22 impact and don't know anyone personally that has I'm just saying what I've heard on the Tube when the M3's were first being released. My M3's came to me new at 110bar 2nd reg. the M4's 100bar. I'm talking about the .25's mind you. I'm not sure how it would like the 300bar to 85bar. I can only assume that it would be fine. I'm not sure about the 177 and what they set that to at the factory before shipping those out. The manual of the m4 tells you you can do 300bar bottles, i believe. I'm not at the house to verify what mines says atm. Or maybe I dreams it up poop now you got me second guessing myself. lol. I'm gonna have to read it when i get home now.
 
you could test it. I'm not sure but I think the M3's 22's come with 85 or 90 bar reg. set from the factory. I don't know for sure because I've never purchased a new 177 or 22 impact and don't know anyone personally that has I'm just saying what I've heard on the Tube when the M3's were first being released. My M3's came to me new at 110bar 2nd reg. the M4's 100bar. I'm talking about the .25's mind you. I'm not sure how it would like the 300bar to 85bar. I can only assume that it would be fine. I'm not sure about the 177 and what they set that to at the factory before shipping those out. The manual of the m4 tells you you can do 300bar bottles, i believe. I'm not at the house to verify what mines says atm. Or maybe I dreams it up poop now you got me second guessing myself. lol. I'm gonna have to read it when i get home now.

dreams it up is correct, along with the notion of needing to buy new bottles
 
  • Like
Reactions: Airgun Al
As far as two regs go, too many guys overthink them. One is definitely if you feel the need to fill a gun to 300b. I can’t argue with two regs on that one. I don’t and won’t fill to 300b but I still prefer two. It’s just too easy to fill a gun nowadays and it’s not like I’m stuck with a tiny tube gun air reservoir. The other reason for two regs or not has to do with how we’re kinda stuck tuning an Impact if you want to hunt with it. If your dive into tuning hasn’t gone that deep, FX just built a gun for you. It’s called the M4. They will save the majority of owners from themselves by simplifying the platform.
 
Juice is not worth the squeeze at 300. Stress on compressor or air tank, gun, increased ES, and air does not behave as ideal gas above 230bar so the extra shot count is lower than expected.
Having never worked with a compressability factor of other than 1 in a dynamic pneumatic system:

A. 200 bar to 150 bar working range made sense for my 10 meter competition pistols.

B. I treat the 250 bar pressure limit stated on my Impact as a MAX pressure limit, NOT a max Working pressure limit.

C. As such if it's going to be 60 to 100°F at the range, I charge the tank to 200 bar. If less than 60°F I charge to 220 bar. So even with thermal expansion I am below 230 bar and the system is working with a compressability factor of 1 or very close to 1.
 
Last edited:
  • Like
Reactions: coastal drifter
Juice is not worth the squeeze at 300. Stress on compressor or air tank, gun, increased ES, and air does not behave as ideal gas above 230bar so the extra shot count is lower than expected.
It is for a lot of people. I get 4 - 5 more magazines per fill 580cc 300bar vs 580cc 250bar bottle in a .25 impact m3 and That's 100+ - 125 more shots that is a lot by anyones measure.