This just takes a drill gun, a 3/8" nut driver bit, and 0000 steel wool.
There are several steps involved in preparing fired cases for reloading. Most handloaders
settle on a few required steps that work for them. The purpose of this "extra" step is to round off and polish
sharp edges caused by case trimming and chamfering of the case mouth. I use a 3/8" nut driver bit packed tightly with
fine (0000) steel wool. After the chamferring process, I spin this tool in a drill gun and insert each case. This
operation only takes about one second per case to polish the case mouth.
Rifle calibers (especially those with heavy recoil) need tight neck tension to hold the bullet securely. The conventional technique is to crimp the case neck into a cannelure groove on the bullet. However, most bullets don't even have a cannelure groove. Those that do usually have it located in the wrong place to allow the handloader to seat the bullet where he wants it.
Bullets have a wide variety of shapes at the rear. I recommend using a VLD reamer (22° - 26° angle) to avoid shaving bullets as they get seated. It also helps to perform this "extra" step to ensure a smooth entrance for the bullet. It you are looking for the best accuracy possible, be sure to also use a straight-line bullet seating die.