I'm shooting my bow 70lbs at 30" draw with 125 grain muzzy 3-blades. If I was to switch to a 100 grain mechanical, how much difference should it make in my groups? Are we talking a foot or an inch at 30 yards? I'm really not satisfied with my muzzy 3-blade broadheads because I can't group them consistently from farther than 20 yards. I'm good with field points all the way out to 30 yards, within a 2" to 3" group pretty consistently.