At one point, I had five .270s, but the fever passed, and I am down to three. Had either three or four 7mm-08s for a while, but they were mainly for the grandchildren when they visited or loaners for guest hunters. We still have five .22 rimfires and a couple of .30-06s.
I have been winnowing the stock in the gun room for a couple of years now, but even at its peak, there was very little duplication of rifles chambered for the same cartridge (other than .270s). I did have a lot of 7 millimeter rifles at one time, but only two were chambered for the same cartridge (7 mm Rem Mag).