You have a long way to go in your anodizing education.
There is no way to explain how to do it in a simple video or on this forum.
Get a general concept here: http://www.caswellplating.com/kits/lcd_ano.pdf
and here: http://www.focuser.com/atm/anodize/anodize.html
Plan on investing at least $500 in a simple aparatus. A battery charger is a poor way to go, but will get you started doing one part at a time. For anodizing entire PB guns, you'll need one of these: http://cgi.ebay.com/HP-Agilent-Varia...item3a5b032c82
To really do entire guns (all the parts, all at once), plan on investing $3000 or more.
If you're really serious, buy an instruction manual: https://www.caswellplating.com/manual/
Buy your dyes and chemicals here: http://www.caswellplating.com/kits/anodizedye.htm
and here: http://www.caswellplating.com/kits/aluminum.htm
After you've learned how, and you have begun to set up your system, join the Caswell forum: http://forum.caswellplating.com/anodizing-questions/
You'll want to experiment on scrap peices befor you ever do a real part... it won't happen the first couple of times. There is a huge learning curve.