Abstract: A method and apparatus is disclosed for using a nozzle to propel abrasive particles with high pressure water. The nozzle has a straight line path for a constant flow rate of air and abrasive particles to a propulsion chamber. A water path through the nozzle also opens into the propulsion chamber, with both the abrasive path and water path intersecting in the chamber. An outlet bore is provided through the nozzle and communicates with the chamber. A high pressure water supply is used and an air and abrasive supply means independent of the water supply is used to deliver a constant flow of air and abrasive particles. The water inlet path accelerates the water in a propelling jet toward and in alignment with the outlet bore so as to impact the abrasive particles and create a high energy abrasive blast through the outlet bore.