From the APOG (Air Power Owner Group's) FAQ:
Air Power had its roots in a Virginia Beach paintball field called Combat Zone, operated by Nick Lotuaco. Nick, along with his machinist Greg Koteski, built all sorts of upgrade parts for Nelson-based pump guns in their spare time. One day the pair got to the point where they had so many pieces they could build a complete gun. Thus the Apex was born, and in the winter of 1987 Nick started the company Air Power to produce it using only one mill and one lathe! Soon after, the Apex Elite (a revised version of the gun) was released and in late ’92 the company went to full CNC. These guns were high quality pieces and were the first ones ever to have what Greg coined the “Venturi Bolt”. The Apex’s were popular, although expensive, and are considered by many to be the finest of their class. The Navy and even the Marines used them in various training exercises.
In February of 1993 Air Power released its first semi, the Vector. Unlike the Apex, however, it was born as less than satisfactory. An extreme gas hog (only 29 rnds/oz.), the Vector had unstable velocity, and the valve tube was prone to failure in < 10k rounds. This version of the gun was later called the Model A. Thankfully, the Model B was introduced the next year and although it outwardly looked nearly identical, internally it was completely revised. Efficiency was increased, the velocity stabilized, and the valve tube was replaced with a solid valve shaft of 17-4H stainless (stronger than titanium). The Vector was available in two versions, the “Backbottle” which was velocity adjusted internally, and the “Thruster” which used an optional external regulator for velocity control. Later that year and in to early 1995 Air Power made the Model C, which is the same gun but came with a bottomline grip. In total there were between 1200-1300 Vectors built.
Unfortunately Air Power hardly advertised the Vector and, due to the bad reputation of the Model A (and the $600 list price), it never really caught on. Because sales were slow production of the gun was discontinued in 1995. Michael Power, their main customer service rep., left sometime in `98 as AP got out of the paintball business entirely by moving the company and halting all warranty repairs. Today Air Power operates as a general construction contractor for the US military.