Power Plenum ~ Taipan Veteran
- Thread starter zx10wall
- Start date
I see a few problems now. Don't know why the link isn't taking you to a accurate place. Here are the specs:
Compression Spring, 302 Stainless Steel, Inch, 0.48" OD, 0.074" Wire Size, 0.873" Compressed Length, 1.25" Free Length, 28.98 lbs Load Capacity, 76.89 lbs/in Spring Rate
I have these springs and would be happy to get you one but you're way over there!
Compression Spring, 302 Stainless Steel, Inch, 0.48" OD, 0.074" Wire Size, 0.873" Compressed Length, 1.25" Free Length, 28.98 lbs Load Capacity, 76.89 lbs/in Spring Rate
I have these springs and would be happy to get you one but you're way over there!
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Made a 3 gram brass hammer weight to test with an ultralight spring. Getting around the same power output as the heavy springs, but I need to stiffen up that valve spring - bounce is pretty ridiculous and it's wasting some air. Factory spring is on the bottom..
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RE: springs - you could go with larger I.D. too, as long as you provide an adequate spring guide.
Do those Taipan Veteran speed dialers that Donny sells have more space for the hammer to slide back? I need to either drill my brass adjuster out or make another one that has a hole in it to get a slightly longer pull in the cocking action.. just need another 1-2mm for my desired spring + weight to be perfect
Do those Taipan Veteran speed dialers that Donny sells have more space for the hammer to slide back? I need to either drill my brass adjuster out or make another one that has a hole in it to get a slightly longer pull in the cocking action.. just need another 1-2mm for my desired spring + weight to be perfect
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Captain's Log, Stardate 2020 zulu. Made a custom valve spring slightly longer and stronger than the factory spring. Saw a consistent increase of 15fps and my shot count increased by at least 5 shots (but only filled to 210bar). Also refaced my brass valve housing slightly deeper with a larger flat face. 
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Captain's Log, Stardate 2020 zulu. Made a custom valve spring slightly longer and stronger than the factory spring. Saw a consistent increase of 15fps and my shot count increased by at least 5 shots (but only filled to 210bar). Also refaced my brass valve housing slightly deeper with a larger flat face.
Very cool.
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1- What's the difference of installing one plenum or two plenum ??
2- Need to know the advantages and disadvantage both of them ??
3- what is the recommended one, if I want to shot heavy slug 25 : 33 gr with average speed 920 f/s and a good shot count ( average 50 shot ) ????
2- Need to know the advantages and disadvantage both of them ??
3- what is the recommended one, if I want to shot heavy slug 25 : 33 gr with average speed 920 f/s and a good shot count ( average 50 shot ) ????
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You could probably achieve that velocity in a Standard with boring / polishing the transfer ports, upping reg pressure, and adding a heavier valve spring - without the plenum extension after the regulator, and instead - put the extensions on the other end in front of the gauge for shot count. My 22 cal does see anywhere from 10-15fps per plenum, but reg pressure needs to be bumped 10 bar or so with each one to compensate.
You can experiment and see if you get an idea balance of power and shot count by moving one or more extensions to the front or rear. The rear will yield the most shot count benefit, given that it can hold 20cc's of air pressurized to 250bar
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Captain's Log, Stardate 2020 zulu. Made a custom valve spring slightly longer and stronger than the factory spring. Saw a consistent increase of 15fps and my shot count increased by at least 5 shots (but only filled to 210bar). Also refaced my brass valve housing slightly deeper with a larger flat face.
How does a stronger valve spring increase FPS? A stronger valve spring decreases valve dwell which means less air being used. So I get the better efficiency result but not the increase in FPS. Can someone please explain?
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Captain's Log, Stardate 2020 zulu. Made a custom valve spring slightly longer and stronger than the factory spring. Saw a consistent increase of 15fps and my shot count increased by at least 5 shots (but only filled to 210bar). Also refaced my brass valve housing slightly deeper with a larger flat face.
How does a stronger valve spring increase FPS? A stronger valve spring decreases valve dwell which means less air being used. So I get the better efficiency result but not the increase in FPS. Can someone please explain?
Probably helps with the drop in pressure when the valve opens. I don't think this is noticed as much with longer barrels, but I'm mainly doing it for better shot count.
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1- how many cc for taipan plenum ???
2- what is the recommended cc volume for taipan veteran 0.22 standard ( reg pressure 135 bar factory set ) ???
2- what is the recommended cc volume for taipan veteran 0.22 standard ( reg pressure 135 bar factory set ) ???
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Mis saludos y mi respeto para todos los miembros de tan tistinguido respetado foro .mi nombre es cesar y soy de rep dominicana y he seguido muy de cerca las discusiones y recomendaciones de este foro y como es evidente tome la decisión de unirme a ustedes en la actualidad solo tengo dos rifles pcp un cometa lynx mk2 en cal 25 y un taipan veterano largo en cal 25 ya que soy relativamente nuevo en esto del aire comprimido pues solia ser cazador de escopeta pero ya estoy dedicado por completo al pcp espero que podamos interactuar en un ambiente de respeto y cortesía tal y como se caracteriza su gran foro y gracias de antemanos por darme la oportunidad de ser parte de ustedes
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En cuanto al tema en cuestion sobre el plenum de ernest estoy actualmente en espera de mi pedido y lo compre solo por el recuento de rondas ya que para el uso que le doy con jsb 25.40 granos a 910 es mas que suficiente claro que es para mis necesidades porque en esto del aire complimido entiendo que se trata de evolucionar nuestros juguetes 
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En cuanto al tema en cuestion sobre el plenum de ernest estoy actualmente en espera de mi pedido y lo compre solo por el recuento de rondas ya que para el uso que le doy con jsb 25.40 granos a 910 es mas que suficiente claro que es para mis necesidades porque en esto del aire complimido entiendo que se trata de evolucionar nuestros juguetes
Bienvenido al foro. ¿No es divertido este juego de PCP?
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I agree. Stronger valve-return spring makes for less power potential but more efficient.
And, once I add extra plenum I like to decrease reg pressure myself. That is, unless I’m going for crazy high power.
With the dual power plenums installed, I could keep power up and drop 30+ bar from the reg. Problem was, with the lesser reg pressure closing the valve and with the Taipan’s weakish valve-return spring, my efficiency went to crap. I found that I need at least 140 bar reg set to keep decent efficiency.
@mtnghost, if you need another test mule for your stronger valve-returns spring, I’m your huckleberry
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@zx10wall - I might have finally made the perfect valve spring. Shot count now is higher than it has ever been, and I'm still seeing a consistent 10-12fps velocity gain over the factory spring. The I.D. is 5.52mm, a bit wider than the spring guides, but there hasn't been any signs of wear on either of the guides after a tin and a half of the monsters, and they seems to say in place well enough.
Where I am really getting tripped up is with the setups using lighter hammer springs and spring guides that I have machined. I've made some from POM-H, PEEK, and the 3 gram weighted brass guide. When I use any one of them, the shots are WAY louder
. I think the heavier springs are just better at absorbing the sound compared to the thinner / wider ones that I've been using. The noise doesn't seem to be any better or worse than it is with the factory valve spring FWIW, but I have a couple of ideas to try out soon that could remedy the situation using POM-C guides and/or shorter hammer springs.
Anyways, I'm going to try and get this all figured out this week. I'll make a few titanium valves with PEEK poppets that have 5.5mm spring guides in the end, and might even test out the design someone posted earlier in this thread to see if it helps with airflow, but I can definitely send you a spring and a valve once I validate that everything works perfectly. I think these valves are going to be indestructible with the materials I have lol
Where I am really getting tripped up is with the setups using lighter hammer springs and spring guides that I have machined. I've made some from POM-H, PEEK, and the 3 gram weighted brass guide. When I use any one of them, the shots are WAY louder
. I think the heavier springs are just better at absorbing the sound compared to the thinner / wider ones that I've been using. The noise doesn't seem to be any better or worse than it is with the factory valve spring FWIW, but I have a couple of ideas to try out soon that could remedy the situation using POM-C guides and/or shorter hammer springs.Anyways, I'm going to try and get this all figured out this week. I'll make a few titanium valves with PEEK poppets that have 5.5mm spring guides in the end, and might even test out the design someone posted earlier in this thread to see if it helps with airflow, but I can definitely send you a spring and a valve once I validate that everything works perfectly. I think these valves are going to be indestructible with the materials I have lol
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@mtnghost, as far as hammer springs, Ernest used a longer spring with a sleeve. Think Vulcan setup. He said that it degreased the cocking effort and cut down on the spring twang.
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Hmmm, I wonder though what ammo and reg pressure he was testing with. I started going down that path to test some springs that had IDs larger than 8mm. They did, in fact dramatically reduce the cocking effort -- at the cost of louder rapport. That "twang" was also eliminated, but the rapport at higher pressures is like an amplified sound of the valve cracking open.
I have some suspicions for why that is, just need to test more this evening. I'd really love to use one of these lighter springs, once I had felt how smooth and light the cocking action was, it was hard to put the heavy one back in. My tune is currently dialed back for 50FPE, getting right about 30-32 shots before falling off the reg (one plenum installed).
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that’s Ernest’s handy work 
How in the hell dis I miss that? 
Great info!!! About what I thought the .25 would do with a 600mm, maybe a little short of what I thought.
I decided against tapping a reg gauge in one of my plenums. It'd be nice to install an EDMU to get finer details, but I didn't want to add another potential leak / failure point to a hunting rig. Plus, the Huma has done a good job of being consistent and fast to recharge for me anyway! Not even sure that I want to try and tune with the factory reg now lol, I had some strings the other night that were all within 0.57fps of each other for 9 shots out of a mag that I ran over my chrono.
Speaking of, this Air Chrony MK3 has also been very good in helping me gauge regulator performance and hammer tuning. I have not had any suspicious readings with it yet, and I have probably put around 600 shots through it thus far
Great info!!! About what I thought the .25 would do with a 600mm, maybe a little short of what I thought. I decided against tapping a reg gauge in one of my plenums. It'd be nice to install an EDMU to get finer details, but I didn't want to add another potential leak / failure point to a hunting rig. Plus, the Huma has done a good job of being consistent and fast to recharge for me anyway! Not even sure that I want to try and tune with the factory reg now lol, I had some strings the other night that were all within 0.57fps of each other for 9 shots out of a mag that I ran over my chrono.
Speaking of, this Air Chrony MK3 has also been very good in helping me gauge regulator performance and hammer tuning. I have not had any suspicious readings with it yet, and I have probably put around 600 shots through it thus far
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