From the research I have done Ross rifle did indeed jam. They were built to very tight tolerances and didn't do well in the mud, but if they were kept clean they were great rifles. The difference between a Ross and enfield is the Ross was built to chamber Canadian ammo which was of a higher tolerances then the british stuff. British ammo was built to all sizes and tolerances but the enfield with it's enlarged chamber could handle all different specs of brass and could be filled with mud and still function. This is why people put rubber bands around new brass for Enfields to take up the slop in the chamber and fire form the brass to fit. Case in point, my no1 mk3 has a sloppy chamber and there's no way my Ross will chamber brass that has been fired by the old no1, but the no1 will chamber brass fired by the Ross. The failure of the Ross was due more to government blunder and less to it being a bad rifle.