Yes.

But it will take a bit of practice to get the "touch" right. And you will mess a few up at first. But, it's .223 brass so a few cases going to the scrap bucket isn't a problem.

A drill bit is designed to advance into the material and so will "grab" the case if you were to try to do it that way. But, a countersink isn't designed to grab and so will only remove material as long as you're pressing it into the material (or pressing the material on to it).

I did once try swaging the crimp but it was tedious on a single-stage press so I tried every variation of reaming I could find. The countersink has been the best combination of speed and effectiveness for me. I use a light touch and so occasionally don't get one reamed enough and the primer hangs up. I just knock the mangled primer out (it won't ignite the primer if you go slowly and smoothly - it takes a sharp strike on the anvil to ignite the primer), throw it away and then use a hand reamer to finish the job.