I have an ACC SDN-6 that needs a host upper. I don’t know much about 300blk, but think it make a decent truck/atv gun for armadillos, coons, possums, hogs, etc. I have a couple SBR lowers, would put a RDS on it. Plan would be subs only. I have 6.5G and 5.56 SBRS and even with cans, they are...