Anything with a break and fast bullets.
The worst I have endured was one round from a Rem 700P in 338 Lap Mag with the factory break. Ears were ringing for 4 hours after that.
*Yes I know a dumb thing to do, but what is done is done![]()
The one with the shortest barrel, possibly.
In general, the larger calibres with short barrels, make a very big bang. My 308 Browning BLR (not necessarily a very large calibre), is very loud. Still, to this day, when I fire in the woods, I am astound at the loudness of the bank.my 45/70 is unbearable with heavy loads. Has anyone actually measured the volume of various cartridges?