probably see a loss of about 400 + or - , but your right its still going to be cooking right along . I have a 7" setup and a 11.5" setup both SBRs , Both great shooters and 6" plates at 100 yards is no problem . I would take a look at Joe bobs 16" barrels for $149 that might help him out and Im sure you could sell that 11.5" barrel for at least that to one of the NFA guys out there
Lord, Make me fast and Accurate. Let my aim be true and my hand faster than those who would seek to destroy me.
Grant me the victory over my foes and those that wish to harm me and mine. Let not my last thought be If only I had my gun ; and Lord if today is truly the day that You call me home , Let me die in a pile of brass.