I use a variation of fish head's method. I FL size the brass, then cut and deburr two slots at 180 degrees to each other, the length of the neck, with a Dremel tool. With a little fiddling, that gives the right tension to hold the bullet just enough to get the OAL to the lands. As mentioned, I repeat it a couple of times to make sure I'm getting consistent results.
It's a very good method.
