my solution to this is foam ear plugs and electronic muffs turned up all the way. Verbal commands are boosted, so the foam doesn't block them, but the shots are clamped down by the elec tronics, and then I still have the foam in.

For those not familiar with active muffs, they are like standard passive muffs, but have speakers and microphones that pass normal sounds. They sense the sound spikes of a shot, and don't transmit the noise through the speakers in the muffs. You can also get them with either bluetooth or a cable jack to hook up to a phone or music player. Many like them for mowing or when working with power tools.

I shoot rimfire bullseye at an indoor rage, and let me tell you, .22LR pistols in a concrete bunker are louder than you think.

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NRA RSO