Pneumatics could certainly do this on 10bar (145 psi) - for example a 50mm bore cylinder at 10 bar will have over 400lbs of thrust. If the spike tip is 2mm x 2mm (unlikely I admit) you have a penetrating force of over 100 pounds per millimetre and Ill let you do the maths to turn that into psi or whatever.

I think the springs may be more work than its worth, althought it may be worth talking to the Diotoir team to find out how they did it for their scoop.

-- Kev