Quite a few years ago I believe Jim Carmicheal did a test to see if big slow,heavy bullets or fast,boatailed bullets would shoot through brush. he made a box that held wooden dowels to shoot through. The end result was that there was no bullet any better than the other and that included 12 ga slugs. All bullets were deflected. The further in front of the target the brush, the further the bullet was off the target. I believe he recomended if the brush was more than 2 ft in front of the target you stood a good chance of wounding or missing a deer completely. With the brush 1 ft away most of the time you would stay in the kill zone.