WS1 should be a .005 choke. If the barrel has no choke in the last 2-3" of the barrel it has been cut or reamed out, but why bother doing that?. If there is .005 choke in the barrel I would be say it is an original. Being 24" is not a deal killer to me for factory made. I shot a borrowed Model 12 that the factory had chrome plated for a rich shooter. Never say never, but you can say odd, until you know for sure.
If it had been say a 26" barrel that they cut to 25" to add a Cutts and then cut again to remove all traces of the Cutts to make it 24", add a rib and refinish the gun at that time I would expect it to be a true cylinder. A 24" factory WS 1 barrel would be an oddity but I know Winchester would make anything if you knew the right person and had money. My father had them make a solid rib 28 ga. model 12 for me after they had refused to make one for several years. He found the right person and got them to do it. Hunting with a fellow who had ordered two model 21's I am sure made it easier to find the right person. Wonder who ever got those guns? Wish I did.
