I have a nice 10/22 with a custom stock, free-floated match bull barrel, and nice Leupold scope.  It's zeroed with CCI Stingers at 50 yards, and was wondering if I should re-zero it for this new Aguila SS ammo.
If you look up this stuff on the internet, it's suppose to be "the bomb."  It's a 60 grain subsonic .22 round designed for Russian Special Forces snipers- and is documented to penetrate 24 inches of gelatin at 200 meters...?  It's suppose to be real quiet too!
Any opinions or experiences?  Looking for using my 10/22 for tactical and hunting applications (read: small varmints, or humans if forced to for defense.)

I have shot it out of my Marlin 39A for backyard utility work a bit. Coup de grace shots on trapped varmints. It works well for that. It is fairly quiet.

I tested it at 50 and 100 yards and found it was ok at 50 (1-1.5") and all over the place at 100. I would attribute this to a slower than desirable twist rate in my rifle. You can buy 10/22 barrels with a twist rate suitable for the longer bullet of the SSS.

Buy a box or two and try it at 50, it might shoot well in you rifle. Whichever ammo shoots better, stick with that.

I would advise cleaning between switching to different ammo during testing. I have noticed when I use my boresnake in rimfires that it will affect accuracy between different ammo.

Anyone else can help?

Originally Posted By Part-time Pork:It's suppose to be real quiet too!

It didn't seem quiet at all to me! Sure, the super sonic crack isn't there, but the 'pop' could still get your neighbor's attention.

Maynard, is right. You will probably need a faster (1-9) twist barrel to shoot the SSS round to its full potential. You might find it accurate enough for close range work, though. I have a few boxes that I want to try in my CZ 452. I'm also looking to test the new CCI Velocitor round.  

www.cci-ammunition.com/new/newcontent.html

what 10/22 setup do you have and what groups do you get at 50yds with stingers also you will notice all subsonic ammo is alot quieter in .22 rimfire I shoot CCi standard velocity but am going to try wolf

I meant what barrel and stock do you have and did you get your trigger worked on?

From what I understand the twist rate of a 10/22 barrel is not optimal for the sss. Try rimfirecentral.com for more info.
I shot about 25 CCI velocitors last week. I like the round, but not the price. To me they are comparable to the CCI maxi Mag.

Yes you will have to zero the gun for the SSS...
or aim high.

The SSS requires a faster twist rate to correctly stabilize the bullet.  It starts to destabilize at about 70 yrds through my 10/22.  Sub-sonic ammo will eliminate the ballistic crack of the bullet breaking the sound barrier, but it still has the associated muzzle blast, and is not really quiet.  The use of a suppressor makes this round almost silent. The only thing you hear out of my AWC Ultra II is the sound of the bolt under recoil.