dale06, same issue here, with one set of Redding dies. No matter how I lube (always sparingly) I get dents. I've used wax, body of case only, One Shot, and some old Lee water soluble lube. Shoulder dents no matter what I do. I think (no, I am not sure) that the die/cartridge combination traps air during the sizing process. I gave up on them, went back to RCBS with a vent hole. No problems.
Exactamundo^^^^ One POS somb that supplies AR barrels and wildcat chamberings insisted on only using Redding competition dies. I asked if they had any other options. Their answer was basically pound sand, we know better. I sold the barrel and said good riddance and went to a different AR barrel and cartridge that is supported by RCBS.