Hey guys. I was wondering how do I get a barrel measuring 4.1mm or 5.1mm inner dia. For steel bbs. I can find any tube which would suffice my needs. From where can I get it or who can make it or how can I make it myself ? It's really important for it to be of precise size as I'm building a full auto...

Does the the tanks volume effect the force we need to apply to build pressure or its the pressure alone which decides it. Force = Pressure x Area. The volume doesn't enter into the amount of force required, but it will affect the amount of work required. Something like my own HEAL is a pretty big l...

Hi guys. Recently I planned to build a full auto bb gun (uses 4.5mm steel balls) operating at 300 psi. Air flow is regulated by a solenoid valve which is controlled by arduino. Here's the question, I've decided to make the air chamber out of a 2" galvanised steel pipe which is 90cm long ( about 1.6 ...