This is REALLY good advice.... When I first started , I prepped 200 LC brass in .223.... Right after that I started shooting pistol a ton and basically stopped shooting rifles , never loaded them... About a year latter I found that brass in a box all bagged up...Just me chattering but if you are just starting to reload I'd start with a pile of range pick up 223. You'll need to practice cleaning brass, trimming, setting up your dies, inside & outside mouth de-burring ( don't forget the steel wool spinner), lubing cases, bumping & measuring shoulders. It's just junk to practice on, you can either throw it away after practice or load and shoot. You won't be out anything if a case or two gets damaged in the learning curve and its bound to happen. Buy the good stuff after practice, I can tell you it really hurts to rumple up a piece of your good brass. And, if I was going to order brass tomorrow it would be Peterson.
I had been reloading rifle for awhile and checked it , I ended up just tossing it in the scrap bucket , it was way over sized from not knowing how to set up the die to minimum size the brass etc... Definitely get some junk brass to learn on when you first start.... I would rather toss $20 worth of brass than have a problem in a $1500+ Rifle... You never really master reloading , you just get better...