My Rifles, in ascending order..
.22 Hornet, .222 Rem, .223 Rem, .22-250, .243 Win, 6mm Rem, .25-06, 6.5x55 Swede, .30-30, .30-40, .308 Win, 7.62x54R, .303 British, 7.7x58 Jap, 8mm Mauser, .350 Rem Mag, .375 H&H Mag, .45-70, and .458 Win Mag.
Most powerful? by fl/lbs? easy, look it up.
Loudest? without hearing protection they are ALL bad. with protection the 7.62and .308 carbines have a real bark. And the .350 carbine is in a class of its own
The .458 is odd, to me, I don't notice the noise, as much as the recoil...