Newbie Question - Subsonic Loads


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fishbulb
February 25, 2003, 05:00 PM
This is probably pretty elementary, but I haven't been able to find a definitive answer.

Do subsonic loads (.22lr in particular) shoot any quieter than standard ones. I would think that they would, and many brands say that they are no louder than a .177 air rifle.

What are your thoughts?

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Blackhawk
February 25, 2003, 05:38 PM
There are two things that go into the bang from a gun. The greatest contribution comes from the burnt gasses escaping from the muzzle. If they're not already supersonic because the bullet is, their rapid expansion when no longer constrained by the barrel and bullet usually goes supersonic with a bang. If there's still unburned powder in them, there will be additional noisy blast.

The second thing is the contribution of a supersonic bullet leaving a sonic boom in its wake.

A long barrel with a mild load can result in the bullet being subsonic and the powder being completely burned before the bullet leaves the barrel. That situation is no different than having the propulsive gasses being compressed air and is relatively quiet.

The .22 rounds you're probably thinking of are way underloaded to achieve that very effect.

Bruce in West Oz
February 25, 2003, 09:42 PM
Yes, they are quieter -- measurably and "by ear".

I do some pest control on a property which overlooks a valley (great for echoes :( ) and with the closest neighbours about one click from the farmhouse. As a matter of courtesy, we use Winchester subsonics. Occasionally, for-the-hell-of-it, we'll fire a couple of high velocity rounds -- you can hear (and feel, actually) the difference.

There is one round we use that has no powder; it just uses the primer for propulsion. That is seriously quiet ---- but totally unpredictable in trajectory beyond about 20 metres.

Bruce

Greg L
February 25, 2003, 10:27 PM
Those Colibri's are great up close aren't they Bruce? :D

Greg

SquirrelNuts
February 26, 2003, 12:44 AM
I shoot Colibris out of my Browning Buckmark and it sounds like an air rifle. I also shoot them out of my Marlin 880SQ rifle and the sound of the bolt snapping is louder than the report for the escaping gases. I have actually fired this rifle and I did not think it actually fired.

-SquirrelNuts

Bruce in West Oz
February 26, 2003, 03:16 AM
Well the ones we get here are called (from memory 'cause I'm at work) Long Zs or something similar -- but same dog, different leg. :D

You can see them through the scope as they curve a-w-a-y and d-r-o-p.

But up close, yep, they're fun :evil:

Bruce

Deadman
February 26, 2003, 07:18 AM
Bruce are Win. Long Z's powderless? I thought that they just had a reduced load?

illuminatus99
February 26, 2003, 07:25 AM
a friend of mine bought some subsonic .22 ammo, we were all shooting the big rifles so he had earplugs in. after firing a few shots he started taking his rifle apart to figure out why it wasn't shooting, then he noticed the spent cases on the ground.......

SquirrelNuts
February 26, 2003, 10:55 AM
That is exactly what I am talking about-you may not know that the gun fired.

The only problem I have had with the Colibri is that it will not cycle in my Buckmark, but I have not tried the Super Colibri. It will also not load properly into a magazine for my bolt action Marlin 880SQ because of its odd bullet and weight-I have to load one at a time, maybe two. Thus, I want a lever action .22, which should solve the problem.

-SquirrelNuts

Greybeard
February 26, 2003, 11:04 AM
To add a bit to Blackhawk's response, typical "subsonic" rounds exit the muzzle somewhere around 900 to 1000 feet per second - just below the speed of sound. They do not have the sharp "crack" associated with bullets roughly 50 to 200 fps faster (varies with such things as barrel length, elevation, and temp.)

Remington makes a common 22LR subsonic load with a bullet weight of around 36 to 38 grains at around 1000 fps. It generally functions quite well in most guns, except some persnickity semi-autos.

Aquila I believe is a Mexico affilliate of Remington and has a few subsonic offerings. Their "Colibri" loads propel little 20 grain pills at around 500 fps or less with primers only. (They are so slow that I've in fact had a few sqib rounds in an old Winchester with 27" barrel - bullets lodged near end without exiting :eek: ).

Aquila has a newer 60 grain subsonic round (around 950 fps) that appears will function best from shorter barrels with faster rates of rifling twist than what many .22s have (1:16 or so).

The "subsonic exit" concept was further advanced several years ago with the development and promotion of what I believe is a specialty .308 cartridge known as the "Whisper".

http://www.22ammo.com/ has info. on numerous ammo brands as well as a specific page that lets one compare at least 8 subsonic loads in 22 rimfire.

Carlos Cabeza
February 26, 2003, 12:41 PM
The little Aguila Colibri round works best from a revolver. I would be cautious shooting them from a rifle because the projectile could become lodged and if shot again could damage the gun or injure you. Yes they are very quiet and definitely will deter some pests from hanging around in your yard too long. I have tried the SSS Aguila .22 also and it has low report but much louder than the Colibri.

Safe Shootin':)

Carl

Greybeard
February 26, 2003, 01:33 PM
Another caution with the Colibris. Being a little shorter than LR and dirty burning, they seem to gunk up chambers pretty quickly, necessitating cleaning before using regular load. Also, to me anyway, they smell bad!

Except for revolvers, I've stepped up a notch or two to the more lethal CCI .22 Shorts or Longs - both around 725 fps and no squib loads - yet.

The Rem. subsonics have considerably more range and are quite accurate out of my Marlins. Anxious to test the Aquilla SSS.

SquirrelNuts
February 26, 2003, 02:10 PM
I have some Aguilla SSS and I do like those too, but they do seem loud. I have not tried the Remington sub-sonic stuff.

I did read the warning about the Colibri's in a rifle, but I have sent several hundred rounds through my Marlin 880SQ, and have never had a problem. I have also put a few hundred through my Buckmark-no problems. They are in fact very dirty and have a funny smell.

-SquirrelNuts

Greybeard
February 26, 2003, 02:57 PM
S. Nuts - Have you been able to group the SSS at 50 yards or better? I've had another thread going recently over in "Hunting" and learned that they may keyhole out of ordinary rifleing. Also interested in "terminal effect" on critters such as crows around 50 yards. Please post on other thread so maybe we don't divert this one too much. Thanks. Greybeard.

SquirrelNuts
February 26, 2003, 03:14 PM
Done.

http://www.thehighroad.org/showthread.php?s=&threadid=10940

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