I generaly don't but I do on Berger bullets that I want to make sure they expand quickly.its said to drop your BC a little bit but the consistancy you gain is supposed to make up for it.
Gun builder Dave Tooley makes them and puts the Tubb name on them. Sinclair has a new one that mounts on a bench. Others also make them. Do a search on this site, these have been discussed at length before.
db