How loud a gunshot is depends on the firearm, but it’s usually pretty loud. Send a single round downrange without hearing protection, and permanent damage can result—even complete loss of hearing. You can eliminate the risk by wearing foamies, quality earmuffs, or modern electronic versions with suitable decibel-reduction ratings. Every experienced shooter knows it’s a basic safety requirement when firing. Recent testing conducted by Widener’s indicates it’s even more important than many realize.
How Loud Is A Gunshot? - Widener's Blog
How loud a gunshot is varies by firearm, but the best answer is that it’s almost always too loud to go without quality hearing protection.
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