I operate sub gun matches hear in the US and get to see HK in action all the time. At a recent match one of our competitors came in with his MP5 and a friend had given him five cartons of HS ammo. this was a gift for allowing the local LEA to use his HK for training. This ammo caused several stoppage's on this gun, this gun has a perfect record for reliability. We switched to FMJ and the problem went away, guess we found out why he got the ammo for free. This may not be typical results with this ammo but it would not feed properly in this gun.