Been shooting the NSA 23 grain .218 dia slugs through my .22 cal. Impact as they gave me the best accuracy and fit my pesting needs. Those slugs I did eventually lube using some silicone after washing in some Dawn Dish liquid. I do feel lubing is good for reducing slug drag and keeping the barrel cleaner. Now that I got my .25 cal Crown Continuum and soon to have slug liner I plan to continue to use silicone lube. I have a variety of NSA slugs to test and they appear to have a hint of lube. Not sure if it is silicone or not but they appear very clean. Do you think I should wash them first and then lube or just roll them around a bit on the silicone treated foam in my pellet tin. Bill