Sniper Rifle Springer. Warning: Plans Only!

[MaxuS the 2nd]

I'm not sure what you mean by a 'wraith system'.

Crash Course in Hammer Valve Workings:

This is the image of a hammer valve that I, myself made. It's not exactly whats inside every Hammer Valve in the world but the basic principles are still the same.



The dark grey circle is a small ball bearing.
The dark 'zig-zag' shape behind that is a spring.
The light grey area is the Hammer Valve body.
The light blue line is the valve stem.

A Hammer Valve works in almost the same way as a check valve does. The air is fed from behind the small ball bearing (Air in) and pushes the ball bearing closed against a sealing face where the ball bearing meets the valve body on the right hand side of the ball bearing).
The spring behind the ball bearing pushes the ball bearing against the sealing face so that it can return to the seated position after being opened.

The valve stem is struck by a 'hammer' (hence the name Hammer Valve). It is not literally a hammer but a weight on the end of a spring, the spring that drives the hammer need not be that strong as not much force is needed to open the valve.

The hammer is cocked and released with the use of a trigger sear (much in the same way that your design work, imagine your yellow 'bolt' is the hammer'). The hammer strikes the valve stem, and due to the inertia of the impact, the valve stem pushes back the ball bearing and allows only a small amount of air out at once.
The air then rushes passed the ball bearing and out through the air outlet (Air out).
This is how many shots are possible through a single filling of the chamber.

Certain hammer valves are used in semi-auto configurations. This can be done by widening the opening in which the 'valve stem' resides. The air not only rushes through the air outlet, but down the space around the valve stem aswell and could recock the hammer if in an air tight environment. Although the valve may need to have a longer dwell time in order for enough air to force the hammer back onto the sear, this would reduce the number of shots per charge.

See this image for details http://www.zdspb.com/media/tech/animations/spyder.gif.

A hammer valve is only really possible with a high pressure air source. Modern PCP Airguns use pressures in excess of 3000psi to achieve relatively good results.

[littlebro05]

Hey again,

If you really want to make a springer sniper or what ever. Just make sure you build from sturdy materials, or buy a sniper if you live in an airsofting country haha...

http://boltsniper.com/BS-6/BS6.htm

This thing uses a plunger system, if you really want to make a springer here is some inspiration. If you ever studied chemistry or physics your system uses somethings called Boyle's Law. Its pretty much like a syringe with a spring and a trigger catch.

Anyway good luck

[BonziPon]

Hmmm, A hammer valve sounds complicated to house. I don't understand how it would look, how it would fit into the stock or whatnot..

A wraith system uses two valves, with an air chamber in between. Fill the entire weapon with air pressure by filling it with Valve A open. Close Valve A. When you want to shoot, open Valve B. When the shot is complete, close Valve B. Open Valve A to recharge the air chamber, then close valve A. When you want to shoot again, open Valve B again.
The wraith system uses equalising pressure as a method of keeping relatively constant pressure. The last few shots do shoot slower, but on your final shot, open Valve A, then Valve B without closing Valve A to realease the entire contents of the tank. The pressure realeased should spike and get either better or the same as your first shot.

Here's a horrible 1 minute diagram.

[Gippeto]

"It is not literally a hammer but a weight on the end of a spring, the spring that drives the hammer need not be that strong as not much force is needed to open the valve. "

Not entirely true. The hammer valve on my co-ax will require more than 300 pounds of force to open it at 3000psi.

@ BonziPon

As to how it MIGHT be layed out, check the link in my sig.

Where did you hear that called the "Wraith system"?

[MaxuS the 2nd]

Not entirely true. The hammer valve on my co-ax will require more than 300 pounds of force to open it at 3000psi.

So how do you intend to cock it with a spring that strong?

All of the springs I've come across that drive hammers are not very strong at all, otherwise you'd never be able to cock it.

[Gippeto]

HIJACK!

Very true.

There is a relationship between spring force, hammer mass, the attendant acceleration and travel distance (hammer velocity).

The physics should be VERY interesting. (Work in progress.)

As for now, I'm using a fairly light spring and the hammer valve works at 1000psi. It doesn't work great, but it does work. (It cracks the valve, bleeds some pressure and then pilots. ie. sBOOM)

At lighter pressures (450psi), it's just BOOM.


I'll be shimming or replacing the spring when I put it back together.

[BonziPon]

On nerfhaven.com. Their forums provide excellent designs and ideas for all manners of homemade weapons.

Edit: seen the link.

[SEAKING9006]

I beg to differ. Nerfhaven is fine for starters, but compared to spudfiles, it's FAR less sophisticated and advanced as far as design complexity, efficiency and ease of production are concerned.

No offense, some of the stuff on Nerfhaven looks damn good, but in all seriousness, 99% of the stuff on Nerfhaven doesn't even come close to touching many of the things that spudfiles users do. I would SERIOUSLY advise you forget everything you learned about pneumatics and physics on nerfhaven, and spend a few hours browsing the forums here to get a feel for different techniques and designs.

And by the way, it's not called a wraith system. It's just two valves. Nearly every single pneumatic gun capable of existing has that setup in some form of another. You wouldn't be able to fill it otherwise.

And if you want an airsoft sniper rifle capable of multiple shots, a far better solution would be a pre-charged cartridge system. Just type it in search and read around for a while.



Wraith system..... I can't stop chuckling.... What 13 year olds won't try to get their name on something...

[Mr.Sandman]

but most of nerfhaven is spring pistons not compresed air or comustible chemicals. the only advantages of a spring piston are: they are cheap, reliable ,easy to build, and more portable with a higher rate of fire

[SEAKING9006]

And unfortunately, that's where the advantages end. It's extremely difficult to coax any kind of useful power out of a spring piston without either a long chamber or a strong piston. And to clear up any discrepancies, by useful power, I mean sufficient energy transferred to the projectile to propel it at least 100-125 feet with limited drop, OR the ability to accelerate the projectile to a sufficient velocity to eliminate the effects of wind on the point of impact out to at least 40 feet.

Also unfortunately, that nixes almost every single commercially available airsoft gun that I wouldn't have to order off the internet, or pay out the ass for.

Which is why a well-made vortex block with a regulated back pack tank or a cartridge loaded sniper rifle is far superior to a spring piston design in terms of acceptable performance. Sure they tend to be larger than most nerfhaven designs, but with HPA or CO2 their size can be greatly reduced, as well as raise their effectiveness in the process.

[Mr.Sandman]

i know that i was just improving on your point that nerf haven is a good starting point

[SEAKING9006]

Yeah, it is. But eventually, we all had to graduate from the school of Daddy's Dremel and Duct Tape to Drill Press and Solvent University.

[BonziPon]

lol. Ouch. I'm 14, and did not invent that system..

I'm not too interested in air, because I'm very inexperienced with it.

I was thinking a spring powered, magazine fed, airsoft gun. But now, I'm confused as to if it is possible or not. I have never made a potato gun nor intend to. ( Also not allowed, no trust between my parents and me when I'm around fire

I'm very interested, however, in using the little talents I have with compressed air, to create a paintball bullpup rifle, with a 10-round tube up top. You know, just to show off to the guys at the course on sunday. 8)

[BonziPon]

Sorry, double posted the same thing.