This got me thinking about making an HPA version of my ball valve strafer. The ball valve only needs to move around 45º for the BBs to pass through, and by gearing it down the travel can be made much less withough making the trigger too heavy so in terms of ergonomics it should be more feasible than my previous attempt.
The advantages of this setup are obvious, you have full pressure in the chamber already so there's no need for pesky detents to allow for pressure buildup - the BB already has whatever pressure you're putting in behind it. Rate of fire will be horrendous but hey, miniguns are cool
besides, with 100 psi I was getting 350-400 fps with steel 0.177" BBs, heaven knows what 8 times the pressure will put out, so short bursts should be enough to shred pretty much anything 
) that I was thinking in terms of gearing it up to make it as practical as a blowgun trigger, watch this space 
I think I'll use the printer cartridge aluminium tubing I've been using for my semi and cartridge experiments of late.
- I had a bit of a quick rummage in the workshop, and look what it turned up 
