They (the factory) will not modify your forearm while it is there for a new barrel. I think the forearm from a .280 will fit on a 12 gauge barrel. I use a 12 gauge forearm on my .280 barrel with no problems. If you wanted, a new or even better, a used 12 gauge shotgun forearm is not very expensive. Perhaps you might consider removing your stocks and keeping them at home if you send the receiver in to have a shotgun barrel fitted. There is an ongoing problem with stocks getting dinged up, and some pretty badly, when they are sent in to the factory. Better still, buy a used 12 gauge barrel and fit it yourself, chances are pretty good it might fit anyway. If your in the New England area stop by Cape Cod and I'll try to help you fit it....<><.... :grin: