Al333,
I use a sauce pan with just enough water in it so a 2 pound coffee can approximatly half full of lube does not float. I slowly heat this on the stove until the lube is melted and pour it around the bullets I have standing upright in a 8x8 inch cake pan.
Once the lube has cooled I punch out the now lubed bullets, put the block of lube back into the cake pan, add more bullets and then heat this in a larger cake pan with just enough water so the pan with the unlubed bullets does not float. slowly heat this until the lube is melted, add more lube as needed and repeat the above steps until you have all your bullets lubed.

Hope this helps,