07-01-2021, 12:50 PM
After having a couple of Faxon Monster barrels and one Green Mountain Monster barrel Id probably buy the 16 Monster barrel. For a general purpose AR-15 the 16 Monster upper make a dandy rifle. The 16 5.56/223 is probably the most popular barrel length in AR-15s. A 16 6.5 Grendel can do anything a 16 5.56/223 is capable of. The 5.56/223 will be a little cheaper to shoot and have slightly quicker recovery time but the 6.5 Grendel has more energy and is a better medium game cartridge. The 5.56/223 is a better varmint cartridge if your concerned about pelt damage.