The present invention relates to a method of depositing using reactive magnetron sputtering a nitride based wear resistant layer on a cutting tool for machining by chip removal. According to the method the deposition rate, td, is higher than 2 nm/s a positive bias voltage, Vs between +1 V and +60 V is applied to the substrate, in respect to ground potential the substrate current density, Is/As, is larger than 10 mA/cm the target surface area, At, is larger than 0,7 times the substrate surface area, As, i.e. R= At/As>0,7 and the distance between the target surface and the substrate surface, dt, is