How Modern Tippman Valves Work
by Billy Goodman

The valve assemblies found in paintball guns manufactured by Tippmann Pneumatics Inc. aren't particularly designed for easy disassembly, and realistically there is no reason they should be. Leaks or other problems with Tippmann valves are rare, and in those rare cases Tippmann is very good about repairing or replacing the assembly as a whole. The company does not recommend owners disassemble the valves. Most owners of Tippmann guns will never see the inside of the valve system. This page is for those who are curious about how modern Tippmann valves work.
 

In the early days of paintball, Tippmann Pneumatics entered the scene with one of the first autoloading paintball guns, the SMG-60. Where pump guns of the day utilized a valve system to release gas to propel the ball, the SMG-60 had a valve which released gas to not only propel the ball, but to also blow the action of the gun back into a cocked position. Early Tippmann guns used a floating valve, which actually opened on two ends to let gas escape and perform the required duties. This system was used on the companies first "box fed" or "gravity fed" semi-automatics such as the .68 Special and Pro am. The rear bolt (a.k.a. hammer or striker) would strike the back of the valve, moving the entire valve assembly forward. As the assembly would impact the rear of the valve tube, plungers on both sides would be pushed opened to allow gas to escape.
 

With later guns, such as the .68 Carbine, Pro Carbine, Model 98, and A-5, a stationary valve is utilized, releasing gas from only one opening. After it leaves the valve, the gas is routed in two directions to both propel the ball and blow the action back into it's cocked position. The valves are made of aluminum, with brass and steel internal parts. In the .68 Carbine and Pro Carbine, the valves are mounted directly in the gun bodies, behind aluminum valve tubes which direct gas through the front bolt to impact the ball. On both the Model 98 and A-5, the valves are mounted inside of a black plastic valve tube, making for a conveniently sealed unit which can be easily replaced as a whole.
 

Standard velocity adjustment on modern Tippmann valves remains the same as earlier models, being controlled by a "restriction" type screw. The screw protrudes into the valve tube, restricting gas flow by blocking the path of the gas after it's exited the valve. Turning the screw in (clockwise) causes it to protrude further into the tube, further blocking the flow and lowering the velocity. Turning the screw out (counter-clockwise) has the opposite effect. As an alternative, aftermarket companies sell kits to allow the external adjustment of tension on the drive (main) spring. Increasing the tension causes the valve to stay open longer when struck by the rear bolt, increasing velocity. Likewise, decreasing the drive spring tension shortens the time the valve stays open, decreasing velocity and saving gas. Since the standard velocity adjustment only affects gas flow after it leaves the valve, tuning the drive spring to affect valve dwell allows for a more efficient use of the available gas. However, the standard velocity adjustment is generally more reliable, ensuring that enough gas to re-cock the action is available, regardless how much is needed for propelling the ball.
 
 

The animation shows a Model 98 valve. When the trigger is pulled, the sear releases the rear bolt. The rear bolt is carried forward by the drive spring and strikes the valve plunger. The plunger moves allowing gas to escape the valve. While part of the gas rushes rearward to blow the rear bolt backwards, part of the gas rushes over 4 channels milled into the outside of the valve, and forward through the valve tube to impact the ball. The valve spring then pushes the plunger back into a closed position.
 

There are some differences in modern Tippmann valves. While the newer Model 98 and A-5 valves have four milled channels on the outside over which gas passes toward the front of the gun, the older .68 Carbine and Pro Carbine valves have two flat sides. Although the internal diameter is the same, due to length and internal parts size differences the Model 98 and A-5 valves have a slightly larger volume capacity than the older .68 Carbine style valves.
 
 


The A-5 marks at least the fourth production model in which this same basic valve system has been used. The simplicity in the design of the modern Tippmann valve systems, along with the use of quality materials, translates into an almost unmatched level of reliability in the paintball industry - which obviously translates into success for the company.