I'm newer to reloading and I'm on a single stage press. I've done .223 Rem and 9mm Luger without blowing myself up so far (knock on wood). I know a lot of people use 300 for subsonic and hunting. I'm planning on just having plinking fun and something that could be useful in a SHTF situation. So for now, just reloading 150gr FMJ target rounds till I decide to make some VMax rounds or something for should the worst happen now a days. Can't hardly find 300 Blackout for less than $1/round, so reloading sounded like a little bit of a cost reducer if I want to shoot 100 rounds a month.

I'm looking for tips or advice on powder, bullets, or even converting brass since I've already been reloading.223 Rem. I'm shooting out of an AR-15 platform. Trying to stay within AR magazine size. Thank you for any help and recommendations.