Try a thorough cleaning a couple of the Tubbs throat maintenance bullets then Dyna Bore coat. I would do this only on a barrel that looks like it is a goner but you have nothing to loose. The barrel may surprise you. Unless it is a known accuracy barrel I would replace it as usually throat erosion goes for a couple of inches if it is bad. A new barrel is almost a sure thing for accuracy if screwed on right. 300 H&H has a cool factor and for some reason kicks a lot less than a Winchester at almost the same velocities.

This may be due to the long sloping shoulders and this could be a factor in throat erosion too. Angle of the shoulders apex is into the throat.

"When you disarm the people, you commence to offend them and show that you distrust them either through cowardice or lack of confidence, and both of these opinions generate hatred." Niccolo Machiavelli