I’ve got a Burris FFIII mounted on an ultimak rail on my 580 model mini, it has the newer .625” tapered barrel, not the older “pencil” barrel. So far it is a nice combination. It will shoot 2” all day long. I put in a .045 gas port and have 1911 buffers fore and aft. I bedded it too. It’s a nice rifle for what I expect out of it.
