WARNING HK21 WARNING HK21 WARNING HK21 WARNING
As Mike Todd pointed out above, the recoil of an HK21 is extreme. About ten years ago while shooting a short burst from my HK21, the retina on my right eye detached. I needed emergency retina surgery to not permanently lose sight in my right eye. And then six months later I needed cataract surgery in that eye. The surgeons and eye doctors I encountered during this saga all stated that heavy recoil shoulder fired weapons shake you head violently and should be avoided at all cost. This is especially true if the shooter is near sighted. Be warned!