different noiselevels for Rimfire guns

[preventec47]

I hear a noticible difference in loudness between the 22 shot std velocity and the
22 short hi velocity.   Same with 22 Long rifle stinger or hi velocity LR vs target or
normal LR loads.   I'm talking about rifles in all cases here.

Can anyone coment about the loudness of the HMR or HM-2  and the 22 mag rounds
compared to the LR hi velocity rounds ?

[torpedoman]

LOUDER much louder.

[preventec47]

So the HM-2 is also much louder than 22 hi vel 22 LR   ?

[notnodak]

The HM2 is close to the same as most LR and less then Stinger/Velocitors but it does have more "crack". Hard to describe till they are side by side. I will say the HM2 is considerably quiter then a HMR and the 22WMR.

[hotrunner]

And I'd almost swear that the .22 WMR is loudest of them all, with the .17 HMR being a little less loud. I'm sure I can tell a difference. Anybody else agree?

[Yak Angler]

I agree. 22wmr is loudest followed by .17hmr, i have never seen or heard a 17mach2 but they should be quiter then .22lr high veloctiy rounds

The way i understand it works for noise levels is. The smaller the bore size the less noise with an equal powder charge. .22lr and .17 mach2 cases are the same size and therefore .17mach2 should be quiter and the same holds true for .22wmr and .17 hmr. same size case/charge . 17 is quieter due to bore size.

[RugerNo3]

Speed of sound is near 1050 nominally.
Low velocity ammo is generally slower or very near that speed. High velocity
ammo is faster then that, hence the faster rounds are breaking the sound barrier and will have a sonic boom (louder).
Ammo loaded for a silenced weapon has to be loaded at the 1000FPS
velocity or the sonic boom will make the silencer null/void.
JD Jones developed the Whisper line of cartridge/rifles for urban sniper settings and the work nicely for depredation work in the cities, both 2 and 4 legged varieties.

[Cottonwood]

I don't have the .17 HMR or HM2, but the 22 WMR is louder than 22 LR for sure.

When target shooting just wear hearing protection.

[gcrank1]

And if you must be quiet, use .22CBs in your rifle. They work great out to at least 25-30yds for me.
In my 24" barrel they seem no louder than my friends air rifle.