James.In my rifles, fouling is virtually non existant with the tsx.I am also able to attain slightly morevelocity with less powder than with other bullets.
The link below shows the remains of a 180gr tsx that penetrated the spine of an elk.
http://www.powerandfury.com/images/tsx1.jpg
http://www.powerandfury.com/images/tsx2.jpg
The remaining weight was 160.4gr.The bullet was fired from a 300ultramag at 3380fps and the range was 200 yards.