Any factory sights on a modern 45-70 are at a serious disadvantage. There is a HUGE selection of bullet weights and velocities for the old warhorse, and their POIs will vary accordingly. The factory has no idea of what the owner will want to shoot and, accordingly, has no idea of what height sights to put on it. That is just the hand the owner is dealt in this case. If what you want to shoot in your rifle doesn't shoot to the sights, then you have to change them. It may be that Marlin will replace the sight with a taller one if they are in a good mood....wouldn't hurt to try.
