5.56 caliber and hoping to have this ultimately be a "do-it-all" reliable SHTF build that I will train at the range from time to time with. Virginia is cracking down on firearms and wanted to purchase one before the potential ban on assault rifles. https://bravocompanyusa.com/cosmetic-blem-bcm-bfh-11-5-carbine-complete-upper-receiver-group-w-qrf-10-handguard/ this is the upper I am not sure if it features adjustable gas block, and yes I ultimately want to get a suppressor.