What NRR do I actually need for shooting?

For indoor firearm use, reviewers across the gun-focused subreddits consistently recommend double protection: foam or flanged plugs (NRR 26-33 dB) under muffs. A single set of muffs in the 22-26 dB range is generally considered adequate for outdoor rifle and pistol use. Marketing claims of 34-37 dB on a single passive muff are widely disputed in lab-tested comparisons.