Nothing special, but it cycles perfectly and eats through ammo. If ammo wasn't so expensive, I'd shoot it more. I have another BCA upper, a 5.56, that is a blast to play with as well.
Lower is printed in Elegoo PAHT-CF. I'll reprint in PPA-CF if it ever decides to crack.
Looks great! 300BLK is definitely a caliber that can be reloaded a lot cheaper than buying factory ammo, especially subs.