.177 cal pneumatic BB gun I am planning to build

[pyrogeek]

Here is a design I came up with for a bolt action BB gun I am planning on building (not to scale, sorry):
http://i7.tinypic.com/21lu96u.jpg

I am posting it to hopefully get some advice. Here are my questions: is there any "ideal" length for the barrel? What kind of chamber:barrel ratio should I use? My air source will probably be a tank charged from a compressor, so I don't want a chamber thats too big. Considering I will be using a 1in valve (the only other option is a 3/4, but I have a couple 1 inchers lying around, I am hoping for very high velocities by the way).

Is there any size pipe I could sleeve the brake line into? Mostly I just want to do that for looks, but also so it will hopefully keep the barrel straighter when handling, and so I hopefully don't poke my eye out on the barrel.

Also, I plan to make a wood stock for this gun to make it more comfortable to shoot, and to help make it a little more solid since it looks like it may have problems otherwise.

Last of all, does anyone have any comments, questions or suggestions?

[M3NT4L]

There is a program called ggdt i think that can fix all your problems and answer all you questions, google it and download it.

[carlbelcher]

If you want to sleeve 1/4" brake line you could use 1/8" Sch.40 PVC it has a .269" ID which leaves you with a gap of .019" that you could probably fill with glue/epoxy.

Also try using GGDT to figure out your chamber, barrel, and valve size.

A wood stock would be cool!

Check out the Crow Killer it's my favorite airsoft/bb gun.