In the 2001 edition of Gun Digest, Rob Lucas wrote an article entitled "Brush-Bucking Bullets That Didn't." Maybe you can find a copy of the 2001 edition at a used book store, as Lucas' article is excellent. In it, he conducted extensive field tests of various calibers, from a .22 rimfile to a .45-70, to ascertain their "brush-busting" capabilities. Based on his tests, the .404 Jeffrey (perhaps not surprisingly, given its 400 grain bullet)performed best. Everything else, including the .375 was so-so, and some where downright awful. Lucas' article is very informative, if you can find a copy of it.