20 years navy in the engineroom. Wear foam earplugs and shooting ear muffs over them. That should reduce the noise to below 60 db. Also keep your mouth shut when you shoot...impact sound can get to your ears through your mouth.
Keeping the mouth shut I think is good information. One ear can be affected more than the other because of the “skull shadow.” Think about how right-handed shooters tilt their heads. So right handers are affected more in their left ears.