Tuning New Artemis p15 dropping fps
- Thread starter montana1
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I am confused also,,, as he was maxed out on hammer adjustment
he back off two full turns and then proceeded to go in 3-1/4 turns ??? magic, I guess
maybe he was maxed out, but the adjuster backed out on it's own while shooting with out his realizing it,,, I don't know.
hard to keep up with new ones, learning what is going on,,, they some times over look what we see, if we had it in our hands,,, we rely on their written observations.
to me , he needs a full shot string, well the end of one , does the velocity go up near the end or does it gently slow down, or drop like a rock?
but the 852-856 fps looks darn good
he back off two full turns and then proceeded to go in 3-1/4 turns ??? magic, I guess
maybe he was maxed out, but the adjuster backed out on it's own while shooting with out his realizing it,,, I don't know.
hard to keep up with new ones, learning what is going on,,, they some times over look what we see, if we had it in our hands,,, we rely on their written observations.
to me , he needs a full shot string, well the end of one , does the velocity go up near the end or does it gently slow down, or drop like a rock?
but the 852-856 fps looks darn good
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The regulator does not need to come out unless it's been out recently. Degas and use the tool that came with the gun to remove the pressure gauge and then the large nut it is screwed into. With it out, you can see the lock nut and the slotted end of the regulator adjustment screw. You'll need about an 18 inch extension to reach things but if you have that, you can work from this end. Action can stay in the stock, scope can stay on. If you've taken the regulator out recently then this will not work, fresh grease on the O-rings of the regulator will allow it to spin and you won't be able to loosen the lock nut.
I would not touch the regulator without determining if the hammer spring is well matched to the current regulator setting. Being able to get to 850 fps is not what you should be settling on. If you are not at maximum hammer spring you should keep going and see where it maxes out. If you are maxed out now on the hammer spring, you'll need to see how long the shot string is to have a guess about efficiency. I get about 70 shots on a full fill. I think I'm a little higher on fpe so you should be able to get at least this many. You can get a good estimate by just shooting a shorter string and note the pressure change then extrapolate. If your velocity increases up to about 890 with more hammer spring then a 850 velocity would be about right to maximize efficiency.
15 bar for 10 shots suggests you should be able to get 60 to 70 shots on a full fill. That isn't great but isn't too bad either.
I would not touch the regulator without determining if the hammer spring is well matched to the current regulator setting. Being able to get to 850 fps is not what you should be settling on. If you are not at maximum hammer spring you should keep going and see where it maxes out. If you are maxed out now on the hammer spring, you'll need to see how long the shot string is to have a guess about efficiency. I get about 70 shots on a full fill. I think I'm a little higher on fpe so you should be able to get at least this many. You can get a good estimate by just shooting a shorter string and note the pressure change then extrapolate. If your velocity increases up to about 890 with more hammer spring then a 850 velocity would be about right to maximize efficiency.
15 bar for 10 shots suggests you should be able to get 60 to 70 shots on a full fill. That isn't great but isn't too bad either.
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I just did a full shot string from 215 bar to 115 bar attached are the results. Velocity dropped when the pressure reached 130 or 135 bar.
Btw from 230 to 115 bar took 80 shots.
My P15 is 2 month old i never opened to fix anything , only used sone cleaningpellets once (around 5).
today i turned the hammer spring 1/4 back Thats it.
Btw from 230 to 115 bar took 80 shots.
My P15 is 2 month old i never opened to fix anything , only used sone cleaningpellets once (around 5).
today i turned the hammer spring 1/4 back Thats it.
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I guess I’m guilty of overlooking the new guy thing. It sounded like out of the clear blue the gun lost velocity without touching a thing. Usually not fixed by turning your hammer spring out then back in. Either way it seems to be ok again. But like you, I’m curious where it’s set in relation to the plateau right now. Is he back to punishing his valve or not. Jim D would know if you need a maxed out spring at 130b. I know my stock spring couldn’t get the job done at 150b.
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Took a closer look at his numbers. Don’t touch a thing until the gun has an issue. Those are good numbers and especially how it came off the reg.
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Bad news guys.
It went back to 760 770 fps from 230 to 200 bar and 15 pellets only.
Turned the HS to the max as it was from factory and fps Strated to go up to 810 fps after 200 bar.
The gun was resting around 7 hours from my last test btw.
Dunno what to do now.
It went back to 760 770 fps from 230 to 200 bar and 15 pellets only.
Turned the HS to the max as it was from factory and fps Strated to go up to 810 fps after 200 bar.
The gun was resting around 7 hours from my last test btw.
Dunno what to do now.
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"Strated to go up to 810 fps after 200 bar."
does the fps go up when the gauge pressure is getting down to 135 bar? then it sounds like a leaking/sticking reg,,,
reg sticks open,, raising the plenum pressure,, making it harder for the hammer to open the main poppet valve
does the fps go up when the gauge pressure is getting down to 135 bar? then it sounds like a leaking/sticking reg,,,
reg sticks open,, raising the plenum pressure,, making it harder for the hammer to open the main poppet valve
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Refer to page one of this topic. Yes, you are taking the gun apart. Twisting hammer screws is not going to cure this illness.
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I will sell it and buy a more stable brand with less headaches at least for 6 month .
Which .22 bullpup do you guys suggest that can shoot slugs and with 900 fps.
Which .22 bullpup do you guys suggest that can shoot slugs and with 900 fps.
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Low velocity at fairly high fill pressure strongly suggests the regulator is not working. If the velocity increases ~100 fps by the time you get to the regulator setting (135 bar, about where mine is) that would confirm the issue.
I can understand your frustration but I don't think you can be 100% confident of no issues regardless of the gun you select. My 3 P35s have had no regulator issues. But my new Air Maks Caiman had regulator issues from day one. It has a Huma regulator. Part of the issue was basically a not well thought through design by Air Maks. The area of the springs in the regulator was not getting to ambient pressure between shots. When that was solved the regulator would sometimes work and sometimes not. Even when it worked the velocity jumped around. So I took the regulator apart and found what I think is an excess of silicone grease on the washers that form the spring in the regulator. Later I found the O-ring at the base of the adjustment screw didn't have enough silicone grease on it (I think, seemed dry) and had failed. But that is all fixed now. The regulator will not hold as low an ES as my P35s if I fill close to it's 300 bar rating but at lower fill pressures it will hold a tighter ES than my P35s. Works fine. Fixing it was frustrating but also educational. My Caiman cost as much as all three of my P35s. It's a nice gun and is machined to noticably tighter tolerances than my P35s but it doesn't shoot more accurately than the best P35 I own.
You'll have to take the airtube out of the gun to get the regulator out which is a pretty complete disassembly. It is good to measure the location of the two yokes that clamp the airtube and barrel together. If you don't get them in the right spot the gun won't cock. But if you measure where to put them it should go smooth. I could do this in an hour or less. It will take you longer the first time but it is not very hard and you do not need special tools. I'd adjust the trigger for sure once you have the stock off. It's easy to make the first stage a bunch lighter and the second stage a bit crisper.
There are good youtubes showing you how to take a P15 apart. I don't think you can find a bullpup as compact and light and still reasonably powerful as a P15. Yours needs a bit of work but it isn't very difficult. I would replace as many O-rings as you can when you are in there. I do not think SPA uses "good ones". O-rings are pretty cheap and having some spares in case it starts to leak later could be handy. I also get the fill port horizontal when I reassemble the gun. I don't know why SPA puts it at random angles. You just thread the big nut in until it's about flush with the end of the air tube and stop when the port is horizontal. There is no "stop" in the airtube.
I can understand your frustration but I don't think you can be 100% confident of no issues regardless of the gun you select. My 3 P35s have had no regulator issues. But my new Air Maks Caiman had regulator issues from day one. It has a Huma regulator. Part of the issue was basically a not well thought through design by Air Maks. The area of the springs in the regulator was not getting to ambient pressure between shots. When that was solved the regulator would sometimes work and sometimes not. Even when it worked the velocity jumped around. So I took the regulator apart and found what I think is an excess of silicone grease on the washers that form the spring in the regulator. Later I found the O-ring at the base of the adjustment screw didn't have enough silicone grease on it (I think, seemed dry) and had failed. But that is all fixed now. The regulator will not hold as low an ES as my P35s if I fill close to it's 300 bar rating but at lower fill pressures it will hold a tighter ES than my P35s. Works fine. Fixing it was frustrating but also educational. My Caiman cost as much as all three of my P35s. It's a nice gun and is machined to noticably tighter tolerances than my P35s but it doesn't shoot more accurately than the best P35 I own.
You'll have to take the airtube out of the gun to get the regulator out which is a pretty complete disassembly. It is good to measure the location of the two yokes that clamp the airtube and barrel together. If you don't get them in the right spot the gun won't cock. But if you measure where to put them it should go smooth. I could do this in an hour or less. It will take you longer the first time but it is not very hard and you do not need special tools. I'd adjust the trigger for sure once you have the stock off. It's easy to make the first stage a bunch lighter and the second stage a bit crisper.
There are good youtubes showing you how to take a P15 apart. I don't think you can find a bullpup as compact and light and still reasonably powerful as a P15. Yours needs a bit of work but it isn't very difficult. I would replace as many O-rings as you can when you are in there. I do not think SPA uses "good ones". O-rings are pretty cheap and having some spares in case it starts to leak later could be handy. I also get the fill port horizontal when I reassemble the gun. I don't know why SPA puts it at random angles. You just thread the big nut in until it's about flush with the end of the air tube and stop when the port is horizontal. There is no "stop" in the airtube.
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put a piece of tissue paper on the breach where pellet loads. check to see if you oring is sealing correctley and not loosing any air out of the breach port!
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For your question, a Vulcan, Cricket or Uragan. Now I have a question. Do you shoot directly into the sun?
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Air is coming out from those holes when i shoot (as you can see in red color air is leaving a mark).
Does sealing the holes makes any difference ?
Does sealing the holes makes any difference ?
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No thats the shroud venting. The problem you have is the regulator. The Artemis p15/p35 is easy to work on, changing the regulator wont take too long.
I even had leaks on my FX airrifles, every pcp will eventually leak
I even had leaks on my FX airrifles, every pcp will eventually leak
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