[Captains1911]

CCI Standard Velocity ammo is going supersonic out of my Ruger 10/22 with a Tactical Solutions barrel. Is this common? I know a lot of people prefer this ammo for suppressor use. It's a shame because it groups extremely well with this rifle, nickel size groups at 50 yds with my Outback II.

[Orkan]

Standard velocity is rated at 1070fps. When its cold out, this can very easily approach or break the sound barrier. A bullet doesn't actually have to "break" the sound barrier to be "louder" than a fully subsonic round in the 1025-1050fps range.

Speed of sound calculator (http://www.sengpielaudio.com/calculator-speedsound.htm)

Use that calculator to determine the speed of sound at the temperature you are shooting at. Then fire your ammo through a calibrated chronograph. Then you'll know exactly where you are.