As a general rule, they are not made to be disassembled
It's a pistol that replicates a real firearm. It shoots a 6mm plastic bb at anywhere from 110 to 500 feet per second (fps).
A semi-automatic airsoft pistol is a pistol which automatically re-chambers a bb, and can be fired again simply by pulling the trigger. They are usually in the form of electric pistols, (usually...
If you want one for less than 30 dollars, here is a link to my favorite one: see the link below
General rule of thumb is buy the best you can afford for what it is you want to do (target shooting, hunting, display, collect, etc..)
Needs to be looked at by a professional
Fundamentals of Contact Shooting Part 1
Fundamentals of Contact Shooting Part 2
Contact Shooting Simulation