It has been my experience that after working with hundreds of No.4 Longbranch as well as the Mk.2 rifles over many years that, with very rare exceptions ,safety failures have been the result of inadequate training, abuse and negligence. The principle cause of failure is a broken or bent safety spring resulting from the incorrect practice of applying the safety with the bolt open. This practice also may result in the scoring of the bolt as well as deformation or fracture of the safety.