I have seen at least three tests in different hunting magazines.One was in petersons hunting but I don't remember which issue.Wooden dowels of various sizes were used in one test and actual branches were used in a couple of others.In one test the two bullets that faired best were a 250gr .338" pointed bullet fired out of a 338win mag,and a 55gr .224" bullet fired out of a 22-250.The larger diameter flat points and round points did not do as well despite being heavier and being fired at lower velocities.The conclusion of all of the tests was that the idea of a brush bullet is a myth.