One Revolver

[Skean Dhude]

I've a Ruger 10/22 and using sub sonics and a moderator my air rifle is louder.

[Timelord]

If I remember right. A variation of 3dB is doubling the sound level - either up or down. is that right?? That would make a gun with a 10dB increase to be x3 louder. That does not seem feasible to me. Uuum!, I will have to look into that sometime.

[CharlesHarris]

The decibel is a logarithmic measure of the noise scale. Zero decibels is the lower limit of human hearing, above 85dB continuous requires hearing protection. Anything less than 140 decibels impulse is safe for short durations. Most firearms except for the least powerful 22 caliber rimfire rifles are above 140 decibels when shot without a suppressor.

An effective suppressor will reduce noise by 20 to 30 decibels, the bery best do better. A 10 dB attenuation is a 10 times reduction in intensity, or 2 times less loudness, 20 dB is 100x less intensity or 4x less loudness, 30dB is 1000 times less intensity or 8x less loudness. Semi-autos "bolt slap" is over 100 decibels all by itself. A 7.62mm FAL is at least 135 decibels, an M4 5.56mm 130 decibels, 9x19mm M9 pistol 130 decibels and a 22LR rifle firiong supersonic ammunition 115 decibels. These levels do not seem so loud because their duration is very short. Some instruments are incapable of providing accurate measures of impulse sounds because of their electroacoustic limitations.

http://www.noisehelp.com/decibel-scale.html

http://www.ncbi.nlm.nih.gov/pubmed/15238316