So I work at a nuclear fusion start-up these days. We have ~1MJ worth of energy storage in 15kV capacitors, along with a hydrogen gas injection system that operates at >500psi. These are solenoid valves that fully dump within 1 millisecond. They are actuated with a ~5kJ, 4kV capacitor bank. I keep t...

https://media-exp1.licdn.com/dms/image/C4D22AQE-OLrsX-uJUA/feedshare-shrink_800/0/1620891745542?e=1623888000&v=beta&t=Kbml65sjTyKUzWdow98xZH9aqoBRdawD3QQfYGoqHS8 "22 metre £1.1 million hyper-velocity gas gun. 100 g projectile, which can reach a maximum velocity of 6.5 km/s using 3 kg of gunpowder. ...

No, I don't have plans to build anything like this soon -- I'm just thinking about how I would do it. I live in a small apartment in the suburbs. I have neither a place to shoot nor to do metal work. I made a small bolt-action cartridge hybrid once upon a time, though. My hope at the time was to be ...

Thanks for chiming in! > What I suggest is trying to keep everything as simple as possible. Have you seen your own diagrams?! :-P Seriously though, I want the operation to be simple for the user, even if it complicates the construction a bit. I got spoiled plinking with my brother's 22 rifle & 9mm p...

A few more thoughts: I looks like Hector's little pistol has 16mL chamber, or ~1 cubic inch. I feel a bit silly for planning a rifle around a chamber with half that volume. So, I eked out a bit more performance by extending the lever arm to 24," the attachment point to 6.5," and increasing the cylin...

I like @hectmarr 's work on these autonomous hybrids. I'm thinking about a design for a single-pump, high-mix hybrid. It seems to me that going for multiple pumps is a waste, since the resistance of the first few strokes is low, so one's arm is getting a lot of exercise just going back and forth. [a...

I like the idea of heating the air by compression in order to get around the sound barrier. That's kinda where I was going with it. I was also thinking that the energy efficiency would be higher than a pneumatic with a similar muzzle velocity. I think spring guns can get up to around 30% or so.

They built a balanced piston valve. Very heavy-duty steel, they've run it as high as 500psi. The barrel is evacuated before the shot. There's a nice shadowgraph image of the shock wave from the supersonic baseball. Discussion of the concept: https://youtu.be/E60G3ba4TUA?t=296 The shock waves start h...

I bet a motorcycle or automotive shock absorber could be turned into a wicked spring rifle... might be on the dangerous side tho! Inspired by seeing one in the dumpster the other day.

Interesting concept, me gusta! The trouble with conventional dieseling spring-guns is the variability of the ignition timing due to fuel mix, which can damage the piston and cause unstable muzzle velocity. Having the ignition occur at a fixed compression could help solve those problems. Metering the...

Damn, that's impressive looking even in CAD. I'm looking forward to the IRL version! Go big or go home, eh?

Very nice work! I would copy this design if I had the space & time to work on airguns again.

What style of valve is used? Any progress on the pump?
Edit: Ok, I have read the latest thread now and I understand the gun. Very cool.

I'd been ignoring friction for the most part. Friction isn't an entirely bad thing for this design, though: the valve-pusher cylinder should *not* travel with the poppet valve -- it needs to stay behind so that the poppet unseats. The whole train of (hammer --> breach slide --> valve pusher --> popp...

Edit: Anatine, I didn't read your response before posting! You scooped me, haha! :oops: Hydrogen would definitely help, although it would be a waste to use it this way without igniting it. :D Dieseling the air gun would definitely help get the energy up -- I've been thinking about how to construct a...

Interesting -- so it's a dump valve, though. Looks to me like the unbalanced force is going to blast it open and keep it that way, just like the QDV. I sketched up an idea for a balanced version of the AirForce Condor. The basic idea is to transfer the hammer strike through a movable cylinder to the...