Last year, rifles meeting certain requirements were legalized for deer hunting the the limited firearm zone in southern Michigan (previously shotgun/muzzleloader/handgun only zone). The requirements are basically the same as the previous handgun requirements: min bullet diameter of .35, min case length of 1.16", max case length of 1.8" straight-walled only. I recently read on a forum (haven't personally verified this) that tapered cartridges are considered straight-walled as far as this regulation is concerned. So my question is this, what kind of velocities might one expect to achieve by cutting a .300WM case down to 1.8" and TAPERING the body down to accept a .358 200gr GMX bullet? Also, what problems might one encounter in doing this? Would there be any advantage over current 450BM offerings?