I've loaded plinking loads without wads in my 45-70. All shots were less than a 100 yards. Did not seem to affected the accuracy any. But the range was minimal. Never tried them at 500+ yards to see what they'd do.
Shoot my win 92 in 44wcf without wads and it does well under 200 yards. I have used wads (poly) when I first started loading for the 44wcf but got lazy and eliminated the wads for quicker reloads. The rifle did not seem to mind any!