I was doing some target 22 target practice and had three different brands of ammo, supersonic Thunderbolt 35 grain, Aguila 40 grain subsonic and Aguila 60 grain subsonic.

The Thunderbolt was the loudest due to the sonic boom, but the 40 grain was noticeably quieter. The exact same setup of rifle and suppressor remained the same for all of them.

Why would the 60 grain subsonic be louder than the 40 grain?