Theoretical muzzle velocity for gas spring air rifle

[MrD1458]

Hello, I was wondering what the highest possible muzzle velocity from a gas piston air rifle would be. I’m curious because I just graduated with a degree in engineering and wanted to construct my own air rifle. I won’t be using pellets as they are very inaccurate at supersonic velocities, so I would be using slugs. Lastly, I want to build a fast shooting air rifle just to put my knowledge into practice and ultimately see if it’s possible, I understand it’s not as efficient as smokeless powder.

[Airnut]

I think that max velocity will depend largely  on your swept volume. The larger your volume the higher your velocity potential will be.
If you want to keep it in a airgun package look to the airgun manufacturers velocity numbers for a magnum springer. Should get you in the ball park. They have been playing the velocity game for years.