I had problems with my valve. Called Tippmann and they sent me a new. They did have a little problem. Try the drive spring first and if that don't work, call Tippmann for a new valve.

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"A positive attitude may not solve all your problems, but it will annoy enough people to make it worth the effort." - Herm Albright

I would also say try the springs first.. then the valve

If it's not an obstruction, it's the springs. Tippmanns use two springs that work against each other: the drive spring and the valve spring.

If the A5 in question ever worked properly, it's most likely a drive spring gone weak. Get a spring kit, or just a new spring, your choice.

If it came like that, the valve spring might be too tight for the drive spring. You could anneal the valve spring. Dissemble the valve, and hold the spring with pliers. Hold over an open flame for a minute, and allow to cool slowly.

Polish the internals too, if you haven't already.

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