You want to be deaf or DEAD? hearing protection is mandatory on the range or when it can be managed, but if you have to pop shots in an emergency situation you will heal up and your ears will stop ringing in a couple of days. Perhaps not from that .454, but most normal calibers. You don't survive wars wearing hearing protection. My cricket noises come from 105mm fire, comming and going. You don't get over that.
Actually, there is no reason why something like the Walker Game ears couldn't be issued as combat gear. It will enhance hearing and protect it at the same time. They are small enough to wear around the clock and could even be fitted with receivers for tac.
I did. We now issue Peltor or Bose headsets for use inside vehicles. It only takes your bell being rung a couple of times from an IED to understand why. Ever executed an air assault mission? Getting off a bird with ringing ears does nothing to help you survive on the ground. Not something I wanted to try, but I lost a plug and and through my equilibrium off the rest of the night. "So there I was" tripping over everything with stereo vision from my NVGs and deaf in one ear traversing a plowed field. Not my idea of fun. Use common sense. If you expect contact, put them in lightly. Light enough you can still hear orders and enemy gunfire, but so your ears don't instantly ring. Some protection is better than none.
I fly twice a week in a Bell 206 L-4... I double up on the hearing protection..ear plug's/ear muff's...