Barrel is 24" as I put a tape on it shortly after I bought it (brand new) and I have never had it chopped.
You'll need to measure it from the face of the breech block/rear of the receiver, otherwise it'll measure right at 24 inches. That's how Ruger establishes the barrel length.
At any rate, you can call Ruger and give your serial number and they can tell you which version it is/was. (603) 865-2442.
It was measured from the breech.
If I wasn't trying to sell it, I may be interested enough to call Ruger. After dealing with them twice previously, I will pass.
PM the serial number to me and I'll call. You've piqued my interest.
I called Ruger and they confirmed everything ENU posted. They also said you should be nicer next time you call them, War_Eagle!!!
As an aside for anyone interested, Ruger said you can request a different style forearm be fitted to your No. 1. The individual with whom I spoke said you need to make the request in writing when the gun is sent to them and
IF they have an available forearm in your requested configuration, they may be able to accommodate you. (He said it would also be dependent on their production requirements.)