I used to punch 2 holes and then connect them with a box cutter, could never get them perfect. Still haven't ponied up for an expensive bag punch. A while back i bought a set of cheap chinese cookie cutter dies, all different shapes. There was one oblong one which is the perfect width for the belt buckle. I've had a set of plastic belt end templates for years and use them to center and mark the hole, then place the die on and smack it with my rawhide hammer. The die I use is a touch short so I just cut the first hole and slide it down a bit and hit it again. They turn out perfect. One thing about the buckle slot is that even if you were off a hair it wouldn't be noticeable.