You want some fun, buy this upper! - Radical Firearms 16 in. 12.7x42 (.936) Upper Assembly

It's the same as a 50 Beowulf. The 50 Beowulf ammo is much more inexpensive than the 450 Bushmaster or 458 Socom, that's a plus. Also, I just had to have a 50 cal in my AR-15. Beyond that, I can hunt with this gun for deer, bear, elk, hogs or anything else and lastly, a 30 round .223 clip holds 10 rounds of 12.7x42 (50 Beowulf rounds). Love my new toy!