I have never needed to swage the primer pockets, although I chuck a standard L E Wilson (RCBS) chamfering tool into a hand drill, and chamfer the primer pockets. The tar can be left in, but it gets on the expander button and has to be wiped off. To clean it, use an oversize stiff nylon bore brush coated with Hoppe's or Shooters Choice or your fave solvent. Water capacity for LC cases has always been very consistent, and measuring error is most of the variation. They hold 54.6 grains of water on average, and the extreme range of weights for 50 (unfired pulldown) that I tested was 54.3-54.9 grains. I fired a 9-shot group using the ones with the extreme capacity, and a 9-shot group with cases which all held 54.6 grains of water, and the groups were within 0.006" of each other. 0.726" center-to-center for the ones with the most case variation, and 0.732" for the ones with no measured case capacity variation. In other words, just load them and go.