How did the Las Vegas shooter get his rapid fire rifle?

BUFFALO, N.Y. (WIVB) – Authorities now say Las Vegas shooter Stephen Paddock had 19 guns with him in his hotel room high above the crowd he attacked.It is believed Paddock modified at least one of the rifles so it could be used to fire automatic rounds.The unmistakable rapid fire of gun shots raining down on concertgoers in Las Vegas indicated to law enforcement, and firearms experts, that Stephen Paddock’s rifle was fully automatic.
Harold “Bud” Schroeder, president of S