Useful construction links
Here are a bunch of links with useful products for construction materials for your gun ammo, and things to just make your gun look cool.
Helpful Information, calculators.. etc...
Might be helpful for barrel sizing etc.. Might be helpful for barrel sizing etc..
A Thesis PDF with a lot of info on gaseous Detonations etc.. Gaseous Detonations
Another Helpful page with more info on Gas Explosions Gas Explosion Handbook
Another good site for metal pipe pressure ratings Metal Pressure Ratings
This has some information on pressures and stuff for pipes. http://www.engineeringtoolbox.com/pipes-pressure-rating-t_40.html
This is a simple to use working/burst pressure calculator http://www.engineersedge.com/pipe_bust_calc.htm
Metals for any purpose you can think off... http://www.speedymetals.com/default.aspx
Industrial supply site http://www.mcmaster.com/
Industrial supply site http://www.grainger.com/
Industrial supply site http://www.mscdirect.com
Good site for pneumatic supplies, and much more http://www.surpluscenter.com/home.asp?UID=2008042000445271
Site for high pressure bike pumps, "shock pumps" http://www.topeak.com/2007/products/floorpumps/pumpmain.php
Marble's up to 52 mm or 2 inches http://www.megaglass.com/