Why is the .22 mag so darn loud?

Loud is relative. Try some full-power .357 magnum rounds and then the .22 mag won't seem so bad!

Btw, a gun always sounds louder when somebody ELSE is shooting it.

The 22 mag generally breaks the sound barrier. Most magnums do, hence the dramatic increase in volume.

The 22 mag generally breaks the sound barrier.

Click to expand...

This.

a gun always sounds louder when somebody ELSE is shooting it.

Click to expand...

And this.

22 WMR is a rifle round, even more so than 22 LR. Since this is in the revolver section, I'm assuming you mean its loud while being fired from a revolver. On top of the speed of sound thing, rifle cartridges out of short barrels tend to be quite loud.

Probably because it's surprisingly high-pressure for a rimfire round. Even .22LR is rated at about 28K PSI for the top SAAMI loads.

Don't know why that would make the .22 Mag seem louder than larger calibers like 9mm that have both more case volume and greater chamber pressures.

I shot a 22 mag. revolver with a 2" barrel, and it was very LOUD. But I don't think it was breaking the sound barrier

The .22Mag and .22LR both run the same pressures, around 22,000CUP. The .22Mag is loud not because it goes supersonic but because it's loaded with a lot of slower burning powder (magnum revolver burn rates) relative to its bore size. Which means a lot of expanding gases through a small hole. IMHO, a .22Mag semi-auto (closed breech) is significantly louder than any .357 revolver. An AMT Automag II will often be the loudest gun on the range. About the only thing louder is a .30Carbine pistol or a heavily loaded .32-20 with 2400 or H110.

22 WMR is a rifle round

Click to expand...

Not really. It shares more in common with magnum revolver cartridges than rifle cartridges and behaves much the same.

It's very pleasant to shoot in a 10" Contender and almost shootable without hearing protection in my 25" CZ Lux, but yeah, in a revolver, it's bad.

I think CraigC nailed the technical reasons.

it isn't that loud at all in a rifle when most of the powder is burned up in the barrel. I had a S & W M-651 with a 4 inch barrel and it was very loud with a lot of muzzle flash

CraigC : +1

steveno:

it isn't that loud at all in a rifle when most of the powder is burned up in the barrel. I had a S & W M-651 with a 4 inch barrel and it was very loud with a lot of muzzle flash

Click to expand...

Double-ditto on that. Try 38 +Ps in a two-inch barrel. I call it my Fourth of July gun because the blast and flash is like a 16" aerial salute. Twelve inch ball of white-hot gases right in front of your baby blues.

I found the flash didn't blind me temporarily when I mounted a laser on it and started firing from bottom-of-rib-cage level. No, that's not hip-shooting because I was using a sight... just way below eye level, was all.

Breaking the sound barrier for something the size of a .22 Mag. bullet is not what makes it loud. I think CraigC said it best:

The .22Mag is loud not because it goes supersonic but because it's loaded with a lot of slower burning powder (magnum revolver burn rates) relative to its bore size. Which means a lot of expanding gases through a small hole.

Click to expand...

The sound of a bullet breaking the sound barrier is not the same as an F-14 Tomcat breaking the sound barrier. Magnum rounds break the sound barrier but it's the high pressures associated with the blast at the muzzle that is loud.

Case and point I have had bullets fly past me breaking the sound barrier, "loud yes.... that loud" No, it was loud enough to make me hit the deck , but that was about it. Think about suppressors... they muffle the muzzle blast (Escaping pressure from the muzzle upon exit)... but if you don't use subsonic loads you still hear the bullet break the sound barrier only giving away your position, it's nothing more than annoying for the people that hear only that but not the muzzle blast which is really what is painful.

***So small bullet, High Pressure, High Velocity out the muzzle creates that effect.

the powder gases (pg) exit the muzzle of the barrel at much more than the speed of sound.

the 22 mag cartridge has more powder, hence more pg pressure when the bullet leaves the barrel, hence more noise.

the shorter the barrel, the more pg pressure in that barrel at the time the bullet leaves that barrel. more pg pressure, more noise.

if the barrel is long enough, the pg pressure will be low enough, hence the pg speed low enough to be subsonic (if the bullet doesn't get stuck in the barrel).

silencers are not made for revolvers because they cannot silence the supersonic gases exiting the barrel/cylinder gap.

fyi,

murf

Same situation with a .30 Carbine out of a Blackhawk.

It'll make even a deaf man scurry for his ear plugs.

Q

Don't know why that would make the .22 Mag seem louder than larger calibers like 9mm that have both more case volume and greater chamber pressures.

Click to expand...

Smaller exit hole, just like putting water through a 1/2 pipe as aposed to a 3/4 inch one, higher water pressure. Think of it as a .22 inch pipe vs a .355 inch pipe.

Jim

silencers are not made for revolvers because they cannot silence the supersonic gases exiting the barrel/cylinder gap.

fyi,

Click to expand...

The silencers bit was just an example to explain something.... also FYI Nagant 1895 actually did have silencers issued in small #'s (Gas seal "revolver"): So to say silencers are not made for revolvers would also not be 100% accurate either.

Again just using "silencers" as an example to explain something. Thanks...

brnmw,

didn't see your silencer post. was just throwing out info on the op's question. nothing personal. nothing is 100 percent!

only effective silencer for a revolver i have ever seen is the towel rapped around the whole gun and hand of don vito corleone in "godfather II".

murf

murf: Sorry about that, thought the fyi was for me.

I have a Heritage rough rider with a 9" barrel. It's not that bad compared to my centerfire pistols. The CCI short barrel loads do shoot better but they aren't even close to a 22 wmr fired from a rifle, even with the 9" barrel.

A 22 wmr fired from a rifle has almost as much energy as a 9mm fired from a 4" barrel

Colt Lawman .357 snubbie 2"

I wear both foam and ear muffs when shooting this revolver. Its like a M80 going off right in front of oneself. The gunfight is over just from the muzzle blast requardless if I hit someone or not.

You don't get something like velocity/energy for nothing. Increased velocity/energy comes at the price of a louder report, no way to change this. As stated previously as compared to a 357mag the 22mag is closer to a mouse fart in its report.

KeithET

As stated previously as compared to a 357mag the 22mag is closer to a mouse fart in its report.

Click to expand...

Not in my experience, especially for an auto like the Automag II.

There is a threshold between a BB gun sound and a loud Bang that is very close in powder charge.

I have designed guns that send 150 gr at 440 fps and sound like a BB gun with no suppressor.

When the escapement gasses from behind the bullet exceed 1 atmosphere above ambient, a super sonic gas ball forms in front of the muzzle. This makes no sound until the gas slows down to the speed of sound. At that point a wave propagates off the ball with amplitude +2A and -0A. That is the very near field and the amplitude drops off with distance. The sound spectrum is that amplitude down to the frequency that corresponds to 1/2 wavelength is equal to the gas ball diameter at the time for first propagation.

What does it all mean?
a) All guns have the same loudness, that is the threshold of cavitation.
2) Bigger guns can make more low frequency, a big deep boom from the 50MBG
3) The size of the gas ball depends on the amount of powder and the volume of the bore area times barrel length.

What does THAT mean?
The 22 mag has a lot of powder for how much barrel volume it has. Pistols are louder than rifles for the same cartridge.

The burn rate of the powder in the 22 Mag is designed to be fully burned up in a rifle length barrel. Out of a pistol, a large percentage of the powder is still burning and the gas is still expanding at a tremendous rate when the bullet exits the barrel. All this equals lots of flash and lots of boom.

This condition is more pronounced shooting factory 223 cartridges out of a short barreled Thompson Contender handgun.

Loudness is all tied to the burn rate of the powder, not the amount, no matter what some say here.