170 grain bullet - Wasn't legal in the 2017 or earlier versions of the rules, either. So, doesn't matter if you haven't read 2018 version. 180 grain is the minimum, and a 185 nominal slug is the lightest any reasonable person would want to load, (in case you get a batch that are running lighter than nominal weight, you will still pass the bullet weigh-in if you are selected for a Power Factor check).
Good luck, GJ