i have one of those mckenzie carbon blocks and have been very pleased with the way it has held up with my shooting field points but i want to shoot some broadheads. i know that is no problem with fixed blades but i shoot the 100 gr. spitfires. can i do this? will it tear up my broadhead. i heard of somepeople who tie their blades together with dentalfloss so that they don' t come open. what do you do.