I was shooting my Contender with 10" .41 mag barrel. It's the loudest round I shoot there. Load was 20gr H110 with a 210 gr bullet. The H110 has a loud report with on odd sense of concussion to it. Hard to describe.
RO raced his golf cart over and in a red faced mode proceeded to explain that rifle cartridges even in a handgun were not allowed and he wanted me off of the range (handgun cartridges, rimfire only). I told him it was a .41 mag with a cast bullet. He was totally shocked. He said that was about the loudest handgun he had heard there and figured I was shooting a rifle cartridge (which would be against the written rules). He had to hang around just to listen to the .41. Actually made him smile. He said he liked loud cars and loud guns.. I got to keep shooting. If anything is louder than a .41 with a stout load of H110 I don't own it.