For years on multiple gun forums I read where someone would not use caliber X because it is just too loud if you had to use it in self defense without hearing protection. If you are like me, you wonder how much of the statements are research based and what is based on something someone else wrote or said without knowing the source of the information and then repeated over and over until it is viewed as fact. With a couple of free hours, six revolvers and a sound meter; we tried to get some more measurable data. The revolvers were selected to minimize difference in barrel length. The shortest barrel was 5.5" and the longest 7.5".
Some background on this, sound is attenuated to different degrees according to conditions present that include things like: indoors vs outdoors, hard surfaces (concrete, steel, etc) vs soft surfaces (carpet, long grass, snow, etc), the distance the meter is away from the sound and so on. The sound levels recorded only have value in comparing one revolver to another. Change any of these variables and you will likely get different numbers but the loudest gun will still likely be the loudest gun just the numbers will be different. The distance was chosen to be a safe place far enough away that the meter will not exceed its range. The test was conducted outdoors, meter operator and shooter standing on concrete and the target was 25 yards away with snow on the ground.
The ammo selected was common stuff similar to what you can get about anywhere. No boutique ammo was used. Surprises? The 10mm was a big surprise. The 327 was expected to be a much bigger spread louder than all else with internet lore and the shortest barrel length in the testing. The 45 Colt was a bit of a surprise as the standard load out of a 7.5" barrel was mid-pack and not the lowest reading. Conclusion: guns are all pretty loud (hahaha) and there is not the real big difference between them we expected. YMMV
Some background on this, sound is attenuated to different degrees according to conditions present that include things like: indoors vs outdoors, hard surfaces (concrete, steel, etc) vs soft surfaces (carpet, long grass, snow, etc), the distance the meter is away from the sound and so on. The sound levels recorded only have value in comparing one revolver to another. Change any of these variables and you will likely get different numbers but the loudest gun will still likely be the loudest gun just the numbers will be different. The distance was chosen to be a safe place far enough away that the meter will not exceed its range. The test was conducted outdoors, meter operator and shooter standing on concrete and the target was 25 yards away with snow on the ground.
The ammo selected was common stuff similar to what you can get about anywhere. No boutique ammo was used. Surprises? The 10mm was a big surprise. The 327 was expected to be a much bigger spread louder than all else with internet lore and the shortest barrel length in the testing. The 45 Colt was a bit of a surprise as the standard load out of a 7.5" barrel was mid-pack and not the lowest reading. Conclusion: guns are all pretty loud (hahaha) and there is not the real big difference between them we expected. YMMV