I loaded some years ago, but no idea what with. Probably either Red Dot or Unique. I have 150 new AR cases for my 625 that I have planned to load for the last 10 years. They are still in the box, minus 6 Dummy Rounds I loaded to go in a HKS Speed Loader for test fit on my Kydex Speed Loader Carriers. Yes I have made a few for a 625 in 45AR using HKS Speed Loaders.
Bullet seating depth is a very big deal with heavy bullets. Get a bullet mold designed for the big bullet to be seated long.
I would then work up from 4.5 grains of Unique. Some old loads get pretty hot. I believe the old Speer manual goes over 6.0 grains of Unique. The bullet you are using, and how deep it is seated taking up space in the case is a Very Big Deal when you start warming up the loads. Work up your loads carefully .
See You At The Range