In a piston cylinder apparatus, hydraulics are used to compress a simple piston cylinder. Large pressures may be obtained, but much greater pressures are possible with a diamond anvil cell.

In the shock wave experiments performed at the California Institute of Technology, a battleship cannon is used to propel a projectile down a six inch barrel filled with H₂ gas. At the end of the barrel is a cap. When the gun is fired, the H₂ gas gets compressed to a tiny volume at the end, rupturing the cap. On the other side is a tungsten projectile in an evacuated tube one inch in diameter. Because the hydrogen expands more quickly that the original projectile was traveling, the tungsten is propelled towards a target with an incredible speed. The pressure created upon impact is of the order of that encountered at the center of the giant planets, although it is sustained for only nanoseconds.