CO2 pistols are similar in their operation to air rifles, as they also propel projectiles using pre-compressed air. In contrast to many air rifles that have a spring pressure reservoir, CO2 pistols often use cartridges or compressed air containers as a power source.
In the field of competitive sports, only compressed air-operated pistols dominate. These typically use ammunition in the form of diabolo pellets with a diameter of 4.5 mm and a weight of about 0.5 g. While recreational pistols can be purchased for around 100 euros, investments of several thousand euros must be planned for precise competition pistols.
Legally speaking, CO2 pistols are to be handled similarly to air rifles: They may be sold if they are marked with the "F in a pentagon" and have the designation E0 < 7.5 J, which means they have a muzzle energy of less than 7.5 joules. This means that no special acquisition permit is required for purchase. However, outside of one's own property or an official shooting range, a CO2 pistol may only be carried with a valid firearms license.