I am building a ar15 rifle with my son. In order for it to be Maryland compliant in the 5.56 caliber it needs to be a Heavy barrel profile. I believe many barrel makers make a heavy barrel profile but not all of them call it that. Maryland deems the M4 barrel profile evil but not the Hbar profile so it's my only option. For easily available cheap ammo we are sticking with the 5.56.
Do you guys have any suggestions?
Excuse the grammar errors I am posting this from my phone.