I have been doing some chrono tests with a "22 browning A-Bolt.  I have measured the actual barrel length to be 20" and the BOSS to be 2".  SO, am I actually shooting with a 20" barrel,or a 22" barrel?    

Your effective barrel ends at the muzzle.  So if it is 20" from the bolt face to your muzzle then you are getting velocity from a 20" barrel.  The barrel on my 7 mm mag is 26" with the BOSS, so I figure velocity from the measured 24" from bolt face to muzzle.  

OK...I figured that much, glad to have some confirmation!  Thanks guys.

Oh, I called Browning and asked the very same question.  Of course, their response was that the BOSS equals the same as rifled barrel.  I figured they would say something like that.  Today many people are velocity crazy, making velocity a key selling point, so they can't be telling people that they will get less velocity.  Heck, if I would have stayed on the phone long enough they would probably have told me that the BOSS cleans the kitchen sink too!

They may have.  It doesn't clean the kitchen sink, but it does WORK!  That's good enough for me.  Hope you like yours as much as I like mine.