30 cm.
The spring device in the gun is an important device for pushing water bombs. The size of the spring determines the power of the gun.
"Water bomb is a soft bullet for toy guns made from soft materials. It is a water compound containing a cross-linked copolymer of sodium polyacrylate. Many Toy guns on the market are currently used. In addition, water-filled balloons and plastic bags used for games can also be called water bombs. It will not greatly affect the tightness of the bullets in the tube. The speed of the 8mm water bullet will be greatly reduced. The 7.5mm inner tube cannot be used. Toy gun made from soft materials. The soft bullet is a water compound and contains a cross-linked sodium copolymer. Used in many pistols.olets toys on the market. Additionally, water-filled balloons and plastic bags used for games can also be called water bombs.