I been wanting an AR platform to shoot cast in for quite a while.
I have a 9mm and might be building a 45 ACP soon.
However I want a bigger thumper.
I bought a BCA 300 Blackout upper that won't shoot ANY cast bullet I've run though it. I have some gas checked bullets on the bench to try in it next.
So my real question is what cartridge, other than pistol, have you have success with in an AR?
350 Legend?
450 Bushmaster?
Those are the two I'm really looking at right now. I want a load that will function the rifle and keep around 2" accuracy at 100 yards.
Or should I build a 10mm rather than a 45 ACP?
Thanks!