Loaded some 6.5 Rem. Mags. for the last 660 Magnum that I bought. Then, took the action out of the stock to insert a rear tang support that I got from Numrich Arms that are only in the Magnums. The gunsmith I took several 600/660's to for the trigger recall removed them and said they no longer fit after redoing the trigger, when I asked him for them he said that he threw them away, YEA RIGHT! Guess what, the one I just installed fits perfectly but you need to put it in place on the rear of the trigger before installing it and the barreled action back in the stock, if you place it in the stock first and then try to install the barreled action, it's a no go.