I use a 30 call can on a 223, 22-250, 6.5 Grendel and both 6.5 & 6 Creedmoor. It's all quiet enough for me.
I swear my 30 call can is quieter on my 10.5" 5.56 SBR then my buddies 5.56 can on his 16" AR. I figure it's related to the volume of each suppressor.
Also, I shot a stupid amount of...