Up or down.

To adjust my PCP rifles, I've always followed the methodology discussed and recommended many times on this forum, and honestly, it's worked for me. Since it worked for me, today I was at the club explaining this methodology to a shooter, and together we got the rifle working properly. So far, so good. But another shooter who was listening came over and immediately told me I was completely wrong.

The rifle in question is an FX King .22 with a 600 mm barrel. In my explanations, we start with a regulator at 75 bar, with the macro in position 13.

18 gr JSB pellets, and proceed with 3 group shots at position 13, another 3 group shots at position 14, and continue in this manner until reaching position 23. What I'm looking for is the smallest or closest group at 50 yards. At the 21 macro setting, we achieved near-perfect accuracy. We then used the stopwatch and measured the velocity at setting 21, which was 940 fps; at setting 22, it was 947 fps; and at setting 23, it was 948 fps. It was slightly increased with micro-adjustment, and the velocity did not increase.

From this, I deduce that with the macro in position 21 and making some micro-adjustments, the deviation can be slightly adjusted. In short, I copied my King's settings and applied them to this other shooter's. The differences are that mine, with the same pellet, prefers 937 fps, while this other guy's prefers 941 fps. And from 250 to 100 bar, I got 115 shots.

IMG_1408.jpeg

Well, I'm satisfied, yes, but this other shooter tells me I'm doing it very wrong, that I have a very low regulator and a soft hammer blow, that it's better to raise the regulator to 100/120 bar and have a stronger hammer, that I would get more shots, more consistency, that the regulator would work better, and I would recover faster. Honestly, I don't know if he's right, and I don't want to ruin my setup either, but I have a doubt. He's talking so confidently and he's getting me into trouble. Maybe he was just a conceited charlatan who wanted to brag about what he doesn't know.

Now I ask, which do you prefer? Would both settings work in theory, or which one is the correct one to achieve the desired FPS?

Low regulator and soft hammer.

High regulator and hard hammer.
 
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To adjust my PCP rifles, I've always followed the methodology discussed and recommended many times on this forum, and honestly, it's worked for me. Since it worked for me, today I was at the club explaining this methodology to a shooter, and together we got the rifle working properly. So far, so good. But another shooter who was listening came over and immediately told me I was completely wrong.

The rifle in question is an FX King .22 with a 600 mm barrel. In my explanations, we start with a regulator at 75 bar, with the macro in position 13.

18 gr JSB pellets, and proceed with 3 group shots at position 13, another 3 group shots at position 14, and continue in this manner until reaching position 23. What I'm looking for is the smallest or closest group at 50 yards. At the 21 macro setting, we achieved near-perfect accuracy. We then used the stopwatch and measured the velocity at setting 21, which was 940 fps; at setting 22, it was 947 fps; and at setting 23, it was 948 fps. It was slightly increased with micro-adjustment, and the velocity did not increase.

From this, I deduce that with the macro in position 21 and making some micro-adjustments, the deviation can be slightly adjusted. In short, I copied my King's settings and applied them to this other shooter's. The differences are that mine, with the same pellet, prefers 937 fps, while this other guy's prefers 941 fps. And from 250 to 100 bar, I got 115 shots.

View attachment 577781
Well, I'm satisfied, yes, but this other shooter tells me I'm doing it very wrong, that I have a very low regulator and a soft hammer blow, that it's better to raise the regulator to 100/120 bar and have a stronger hammer, that I would get more shots, more consistency, that the regulator would work better, and I would recover faster. Honestly, I don't know if he's right, and I don't want to ruin my setup either, but I have a doubt. He's talking so confidently and he's getting me into trouble. Maybe he was just a conceited charlatan who wanted to brag about what he doesn't know.

Now I ask, which do you prefer? Would both settings work in theory, or which one is the correct one to achieve the desired FPS?

Low regulator and soft hammer.

High regulator and hard hammer.
I won't even try to justify why it works but I've run across 1 thing with all my PCPs in various calibers (all fac power) 150bar. It just keeps ending up that way. I prefer a heavy hammer and high pressure as it ends up. It's personal preference on the shot event.
 
I've never tried this. Maybe it would make my Caiman a bit quieter. If I understand the "high reg high hammer" you are deliberately going well past the point of highest velocity for the regulator setting to slow the pellet some. I guess I used to do this a little bit on my Avenger after noticing an accuracy improvement. Or are you using a hammer setting much more than 5% under the maximum velocity setting for that regulator setting? I do not own any FX airguns and I am not comfortable I understand the settings discussed.
 
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To adjust my PCP rifles, I've always followed the methodology discussed and recommended many times on this forum, and honestly, it's worked for me. Since it worked for me, today I was at the club explaining this methodology to a shooter, and together we got the rifle working properly. So far, so good. But another shooter who was listening came over and immediately told me I was completely wrong.

The rifle in question is an FX King .22 with a 600 mm barrel. In my explanations, we start with a regulator at 75 bar, with the macro in position 13.

18 gr JSB pellets, and proceed with 3 group shots at position 13, another 3 group shots at position 14, and continue in this manner until reaching position 23. What I'm looking for is the smallest or closest group at 50 yards. At the 21 macro setting, we achieved near-perfect accuracy. We then used the stopwatch and measured the velocity at setting 21, which was 940 fps; at setting 22, it was 947 fps; and at setting 23, it was 948 fps. It was slightly increased with micro-adjustment, and the velocity did not increase.

From this, I deduce that with the macro in position 21 and making some micro-adjustments, the deviation can be slightly adjusted. In short, I copied my King's settings and applied them to this other shooter's. The differences are that mine, with the same pellet, prefers 937 fps, while this other guy's prefers 941 fps. And from 250 to 100 bar, I got 115 shots.

View attachment 577781
Well, I'm satisfied, yes, but this other shooter tells me I'm doing it very wrong, that I have a very low regulator and a soft hammer blow, that it's better to raise the regulator to 100/120 bar and have a stronger hammer, that I would get more shots, more consistency, that the regulator would work better, and I would recover faster. Honestly, I don't know if he's right, and I don't want to ruin my setup either, but I have a doubt. He's talking so confidently and he's getting me into trouble. Maybe he was just a conceited charlatan who wanted to brag about what he doesn't know.

Now I ask, which do you prefer? Would both settings work in theory, or which one is the correct one to achieve the desired FPS?

Low regulator and soft hammer.

High regulator and hard hammer.
HELLO.. if I’m not mistaken your rifle liner 600 is for slugs, let me explain, the twist rate on yours is 1:16, vs, king 500 liner is 1:24.
Which means 1:16 is faster spin for slugs, 1:24 lower spin for pellets. So for the reg setting I recommend you start in 100 for pellets
At #13, for pellets you don’t need a lot of speed i mean you shooting 18 grains , if you decide to use heavier pellet like 25 or higher
Increase you reg 5 bars increment and your macro wheel too, the fine tune with your micro adjustments.

Now Slugs its a little different, they need more speed . I have one king too 600 for slugs and I’m shooting zan 33 grain at 990 .
Just IMHO. BE SAFE
 
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HELLO.. if I’m not mistaken your rifle liner 600 is for slugs, let me explain, the twist rate on yours is 1:16, vs, king 500 liner is 1:24.
Which means 1:16 is faster spin for slugs, 1:24 lower spin for pellets. So for the reg setting I recommend you start in 100 for pellets
At #13, for pellets you don’t need a lot of speed i mean you shooting 18 grains , if you decide to use heavier pellet like 25 or higher
Increase you reg 5 bars increment and your macro wheel too, the fine tune with your micro adjustments.

Now Slugs its a little different, they need more speed . I have one king too 600 for slugs and I’m shooting zan 33 grain at 990 .
Just IMHO. BE SAFE

I only shoot pellets. I don't have any place to shoot, except at the shooting club. The only one where I live has a large gallery that is 50 meters long and is shared with all the shooters.Since it's a short distance for slugs, I'm using the 18g/15.89g JSBs, and I also agree that the King's 600mm barrel is optimized for slugs, but it works very well with heavy pellets.

I'm very satisfied with my current setup; I get very good accuracy and plenty of shots.
The question is about the PCP's settings. I currently have the regulator at 75 bar, the macro at 21, and the micro at 2.3.
That is, I have a low regulator and a loose spring.

Another configuration could be:
a higher regulator and a tighter spring
and the question is, which of the two configurations is better, more advisable?

The point is that if I can get the ideal velocity for the pellet I want with a low regulator and a soft spring, it doesn't make sense to work with a high regulator and a tight spring; this way, the rifle has more stress and more things can go wrong.
 
Spring disc regulators are adjustable NOT variable and once set should be left alone.

They may be adjusted to increase output pressure with the rifle at operating pressure because you are decreasing the force acting on the inlet pressure valve seat during the adjustment.

With the rifle at operating pressure, decreasing regulator output pressure drives the valve stem into the inlet pressure valve seat, which if done often enough will score the valve seat and the regulator will no longer maintain set pressure. Before lowering the plenum regulator output pressure the plenum should be degassed.

As such, starting at a lower plenum pressure and adjusting UP during your pellet testing/tuning process is much easier on the regulator and requires less air and less time running your air compressor.

If you hear a loud metallic "PING" when an Impact M3 is shot, the shooter is hammering the crap out of the valve stop using a high plenum pressure and hard hammer.
 
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To me it sounds like a little bit of a mess. 2500 dollar gun and tuning without a chrono. Can’t imagine that myself. Personally with the fx guns I hardly use the macro when tuning. The bread and butter is in the micro. I will use the macro only to save time over using the micro. When tuning up trying to find plateau velocity for a reg pressure one can use the macro to skip ahead a little. Don’t use it as a main source though at all. I do agree working up low to high is the way to go though. Focus should be on the micro adjuster and a chrono is absolutely 100000000% a must.
 
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A mí me parece un poco caótico. Una pistola de 2500 dólares y una puesta a punto sin cronómetro. Ni me lo imagino. Personalmente, con las pistolas de efectos, casi nunca uso el macro al afinar. La clave está en el micro. Solo lo usaré para ahorrar tiempo. Al afinar, intentando encontrar la velocidad de meseta para una presión de regulación, se puede usar el macro para adelantar un poco. Sin embargo, no lo uses como fuente principal. Estoy de acuerdo en que ir subiendo de bajo a alto es la mejor manera de hacerlo. La atención debe centrarse en el microajustador y un cronómetro es absolutamente imprescindible.

1st - I start the adjustment with a low regulator, 75 bar, and the macro position at number 13, which is recommended by FX. I don't use a stopwatch for this step.

2nd - I shoot three times at the same point. I'm looking for precision, single-hole shooting. I'm not looking for speed at this step.

3rd - I repeat the process at each macro position from position 13 to position 23. Throughout the entire process, I only change the macro position; I don't touch the micro at all.

4th - At macro position 21, the PCP shoots single holes, now using a stopwatch, and measures 941 fps.

5th - I want to know if I am at the top, I put the macro to position number 22 and stopwatch, I get 975 fps, I put the macro to position 23 and stopwatch, I get 978 fps. As the macro wheel has no more positions I give it 3 clicks with the micro and stopwatch, I get 978 fps, I am a little above 4% of the maximum power with the regulator at 75 bar.

Conclusion: With the macro in position 21 and the micro in position 2.3, I get incredible accuracy—that is, I have a low regulator and a loose spring.
This tuning allows me to use a pellet weight x with complete accuracy, and since the macro is in position 21 and the micro in position 2.3, I can shoot other pellets of lower weight by simply adjusting (lowering) the macro wheel and making micro adjustments.
 
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