I 've been reading in a few different books about actions used for building double rifes. Some sources suggest that some sort of back action sidelock, either hammer or hammerless, is better because less metal is removed from the frame. This makes sense, but it would mean more wood removed from the stock; not good on a heavy recoil rifle. Are these considerations more theoretical or are there examples of failed double rifles that can cleary be attributted to design flaws. After all there are good examples of the various designs.