Solving pump-pistol issues
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jackssmirkingrevenge
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It would work as drawn, certainly - but in terms of complexity, you're not really gaining anything by having two pumps in my view.
hectmarr wrote:You have to make many weapons, because this field is long and short life
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jackssmirkingrevenge
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Sure, not just yet though as I'm at work and don't have access to GGDT. What projectile weight?jean wrote:@jsr can you please ggdt it for me?
100cm barrel 8mm
chamber 3ml @100bar
HGDT is for combustions and hybrids... actually, the single stroke mechanism is very interesting for a portable hybrid!and the same with hgdt.
Let's say you 50cm long chamber tube, and a barrel/pump filler with a stroke of 45cm - that would take you to enough pressure for a 10x hybrid
I was thinking along these lines here.
By having a 1x mix in a syringe and using that to pressurise a cartridge, any pressure you reach would technically be at the right ratio. Using it manually would naturally limit you to the pressures you can achieve through the pressure you can exert, so a possible solution to this would be modifying the syringe to enable the plunger to be pushed by air pressure
Coupled with Brian's concept here, hmmm...
Replace the burst disk pilot with a check valve, add some ignition points and a quick syringe squirt of butane/propane before inserting the pump head... profit!
I'm sure this is exactly the sort of brainstorming he intended to happenbrian sorry for the highjacking
hectmarr wrote:You have to make many weapons, because this field is long and short life
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POLAND_SPUD
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heh not a bad idea - sounds worth tryingReplace the burst disk pilot with a check valve, add some ignition points and a quick syringe squirt of butane/propane before inserting the pump head... profit!
ohh and a metal on metal detent mechanims would be ideal for this application
edit
now I am wondering... it would make more sense to reach higher pressures right? why choose 10x when you can 30x...
but then again isn't it possible to get the mix to auto ignite?
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jackssmirkingrevenge
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I've been thinking a lot about that lately, it seems that with pellets it's the best solution. O-ring detents are a dead end because of the head and skirt, works for BBs but not for pellets.POLAND_SPUD wrote:ohh and a metal on metal detent mechanims would be ideal for this application
Jamming a 0.22" pellet into a 5mm hole on the other hand, that holds some promise...
Say you have a 1 metre long pump tube, and a 5cm long cartridge, that's 20x easily...now I am wondering... it would make more sense to reach higher pressures right? why choose 10x when you can 30x...
I don't think so, propane has an autoignition temperature of 470ºC, you're not going to reach those levels unless you drop an anvil on the pump plunger from a great height...but then again isn't it possible to get the mix to auto ignite?
hectmarr wrote:You have to make many weapons, because this field is long and short life
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jackssmirkingrevenge
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Here it is in GGDT assuming an 8mm steel bearing projectile and you can get to a pressure of 750 psi / 50 bar.
Note that at that pressure and using a 20mm ID chamber you would have to push down with around 125kg of force... so start eating
Note that at that pressure and using a 20mm ID chamber you would have to push down with around 125kg of force... so start eating
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hectmarr wrote:You have to make many weapons, because this field is long and short life
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jackssmirkingrevenge
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Just thinking aloud here, hmmm...
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hectmarr wrote:You have to make many weapons, because this field is long and short life
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Labtecpower
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Should work I think, however the opening speed of your valve will be hugely limited by being fixed to the pulling rod..
you aren't going to manage a 1 ms. opening time on this one
you aren't going to manage a 1 ms. opening time on this one
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jackssmirkingrevenge
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With 1000 psi in the chamber giving a hand, I think it wouldLabtecpower wrote:you aren't going to manage a 1 ms. opening time on this one
hectmarr wrote:You have to make many weapons, because this field is long and short life
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Brian the brain
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Looks like that thing would pop as soon as the balance is broken...
Gun Freak wrote:
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!
Can't ask for a better compliment!!
Oh my friggin god stop being so awesome, that thing is pure kick ass. Most innovative and creative pneumatic that the files have ever come by!
Can't ask for a better compliment!!
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jackssmirkingrevenge
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My thoughts exactlyBrian the brain wrote:Looks like that thing would pop as soon as the balance is broken...
might be worth building but lots of other projects on the table at the moment.hectmarr wrote:You have to make many weapons, because this field is long and short life