It will fit but just barely. If you don't already have the chassis I would recommend waiting a month as we're opening up the barrel channels on them. If you have the chassis, it would be best to keep the barrel a bit under 1.25.
Regarding the balance, it will be front heavy in any stock or chassis, ours or others. For a W-3, the weight is toward the rear (machined aluminum) so that will help with balance. You can add one of our new steel bag riders or LOP spacers at the back with either of our chassis so that will help with the balance. These will be ready to ship in a couple weeks.
Thank you for your business!
Justin