How did he get 13 shots off? Very simply, he reloaded. There are no .270 Winchester or Weatherby caliber rifles commercially produced to handle a magazine with over 5 shot capability. It's not your decision to decide what is or is not suitable.  A good man or woman can pump ten rounds out of a lever action rifle or a pair of revolvers just as fast or faster than a person with a semi automatic firearm.  In fact so can a well trained man with a bolt action. Watch https://www.youtube.com/watch?v=BXPB8I1FuF8 Please educated yourself.