Yes you can use them and yes DO clean the lube off. I use Coleman Fuel; poor bullets into a coffee an and cover with fuel. Let sit for several hours and then swish around and dump off fuel and residue. You might have to do a rinse with more fuel here. Dump the bullets out on an old towel, spread out and let air dry (in the Sun makes it quick). I used some commercial 250 gr SWC .452s in my TC Blk Mtn Magnum .50 with Knight black sabots. With FFG 777 I pushed them to 1700 fps with 2-3 MOA (5 shots with out cleaning) at 100 yards. That was about max velocity before accuracy deteriorated. That would be death and destruction for a hunting load. I was going to hunt deer that load, except I'd cast my own bullets with a Lyman Keith SWC, but Oregon outlawed the use of sabots.
Larry Gibson