Thinking about putting a factory 700 in the large lug Bravo?? Would this save me problems later if I ever wanted to do a barrel/recoil lug swap? Or would it cause me headache now?
Would likely cause you no problems at all short of the extra space filling up with lint.
Seriously, it's the rear face of the recoil lug that's meant to make contact with pocket in the stock/chassis so there's no effect having a factory-sized lug in a larger-than-necessary lug recess.