I have not even had a fast fire 3 in my hands but am thinking about putting one on a win 1300. What all does it take to mount one to the gun it is already drilled and tapped from the factory?
I believe you need the Weaver base for the Winchester 1300. It's the model 416T (double check that)
Amazon sells it pretty cheap. Just to make sure, call the Burris help line and they will correct me if I'm mistaken. I installed the FF3 on my Benelli Nova and really like it.