Looks like a 6 1/2" barrel to me. Did you measure from the front of the cylinder to the end of the barrel? Usually, but not always, the 6" barrels have a Patridge front sight and the 6 1/2" barrel has the red ramp front sight.
Is the knife in the trigger guard a small Case? Stockman pattern? Other? It looks lot like a small Schrade with Staglon handle scales, but the shield in the handle looks like the Case oval.
As Leonardo and others have said, that is a very pretty gun.
Muley's info on front sights was new to me. I can't offhand recall seeing a ramp sight on a Model 27, only on M-28's. I've had two six-inch M-27's and a 6.5 inch pre M-27. All had Patridge sights.
And all shot fantastically well. Six shots in a single jagged hole at 25 yards from "offhand" was common.
I'd have bought others, but prefer stainless guns for real world use. I have no safe queens.
In my observation a ramp on a 6" 27 is exceptionally rare. On the 6.5" guns it's about 50/50 ramp and Patridge. That does look like 6.5 to me so a 27-1 with that barrel length would be very, very rare because the -1 was made for such a short time.
The factory polish job and resulting bluing on your gun is superb. The Colt Royal Blue finish could not be any better than the bluing S&W did on your gun.
Larry
I've had several 27's and pre 27's and and never got them to shoot into one jagged hole at 25 yards , especially offhand. What kind of ammo were you using ?