4 a friend
I\’ve done them with and without lube

I size bullets as part of my reloading process because I believe I found a slight variance in the bearing surface diameter when I sized a box of bullets as an experiment

I only size jacketed bullets to reduce any size variance in the rounds. (usually less than .001\” if it exists)
I prefer to just run them without (no lube to wash off)
I will lube if greater force is needed to size them

I haven\’t done any cast bullets so I cannot speak to that (Lee does recommend their liquid Alox for cast rounds)
RMR, Speer, Hornady, and Sierra make bullets better than anything I would or could cast