Hey check out the new bolt on kit to convert almost any blowback marker into an air ram gun. It operates at 250 psi input to vert reg and around 75 out the LPR. Shoots 20 -30 BPS (depending on if you have an eye or not). So if you have a Black Dragun, Pirahna, or Spyder and you want it to shoot like a timmy, check out Draguns site!!
http://dragunempire.com/news_detail.php?id=21