Want to build a new pcp air rifle

[beastmode986]

ok so i have decided on my next project and i am building a pcp air rifle! My goals i have are the following
accurate
700fps but can be adjusted for higher velocity
operates on a co2 tank or hpa(regulated)
efficient

So far im pretty much dead set on .177 as my caliber but maybe .22 but because of the high availability on .177 pellets in my area it makes that my first choice. I will probably make this a semi auto because if used bolt action you guys would reccomend a hammer valve but it would be difficult to make and so would the hammer/sear as well, But then again a bfb wouldent be easy for me either. As of now itll be a semi automatic. Right now i have a 1/4 qev made of steel and a .177 caliber barrel that is un rifled(i might buy a rifled on for improved accuracy) you guys are now probably gonna say ''get a slide valve'' which i might do but here are my questions

can someone give me a link that will show me how a bfb works and or how to build one? i saw wyz's video but i didnt understand the design that well(good video by the way)

what are my options for a semi auto? besides qev+ slide valve?The slide valve is kind of hard to add a trigger to. thanks!

[wyz2285]

use a 3-way instead of silde valve.
bfb doesn´t fit with accuracy, it will destroy the pellet. If a f**king hammer valve is too complicated for you, don´t start this "new project" at all, you will be wasting time and money.

[sagthegreat]

for pcp, make a hammer valve, there are plenty tutorials on how to make one using a blow gun, also if you use an electronic solonoid to trigger the hammer valve, you now have full auto!

[beastmode986]

ok thanks for the replies, I could build a hammer valve but it would be difficult because it would be my first time building one. Also how would i make a semi auto without a bfb it dosent seem like it would feed correctly although i could still make this a mag fed bolt action. I was considering full auto but i still dont have a proper feeding system thought out yet. I would use the hammer valve i took out of a tippman 98 custom but it has a blowback mechanism and that would waste air and to rebuild the blowback system just seems like alot of extra work but the good part is if i do end up using it i can run unregged co2 to it

[sagthegreat]

a Simple blow forward breach, for the hammer valve, its just a blowgun with a hammer or solonoid pressign the button for half a second, on one end of the blowgun is the air tank, on the other is the barrel/ammo feed/blow forward breach

[beastmode986]

well now that i think about it a hammer valve dosent seem to hard to make, but wouldent a hammer valve with the bfb have the same affect as a qev with a 3 way valve and bfb? wyz said a bfb dosent fit with accuracy


how would i hook up a solenoid? i have a few already that i got from sprinkler valves, would i just run it to two 9 volt harness and hook up a momentary switch? then mount it to the back of a hammer valve?

[sagthegreat]

Yes, you might need to mess around with it a little so it is more powerful

[beastmode986]

ok so will a solenoid from a sprinkler valve work? mines being king of weird what part would act as the hammer? and would a bfb destroy the pellet???

[beastmode986]

ok , sorry for thee double post but i guess i made a hammer valve. I took a blow gun and cut it down a bit now ill epoxy a 1/4 in elbow into the top and another onto the bottom and then ill attach my air resevoir and my barrel.


I know this is a bad bad drawing but it will do . Is this how a bolt action design would work ? mainly red=bolt blue=hpa green = spring gray =pellet and black is the barrel and air chamber outline




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[Gippeto]

That's the basic idea.

[beastmode986]

ok thanks and i already have a magazine system in mind .now to go to the hardware store

[sagthegreat]

the part of the solenoid that actually moves is the hammer, if you use it in combination with the blow forward bolt, you may need to tweak the timing of the solenoid so the bolt chambering the round and the valve letting out a burst of air are at the same time, or else it might jam

[beastmode986]

ive decided to go with a bolt action due to the fact i havent mad a pcp before ill keep it simple for now. However i dont get how to hook it up to the blow gun. i have looked up animations but the solenoids i have dont seem to work as they should can you give me a link to an example please