I am new to bow hunting and have been practicing with field tips all Summer but now figure I'd better try with some broadheads as our bow season in Minnesota is about a month away. I've been using a bag target I bought from the local pro shop but they tell me that will tear up the bag and that I should buy a foam block target. I trust them on the first account but don't really want to invest in another target that I won't use that often. Any suggestions on alternatives or homemade targets that could handle limited practice with broadheads? Also, will practice dull the blades and if so, how should I resharpen them? Thanks!