If i was you i would use a rifle. It also depends on the caliber you are shooting. I shoot 165 grain 30-06 and i have no problem with brush. also my dad shoots a 30-30 which is a really nice brush gun. But i personaly think that 100 gr. is to little and would suggest to use a higher such as 130 or 140 if u still wanna shoot low grain. if you dont care i would suggest 150 or 165 grain.