I may be an idiot, but I have been looking at upper assemblies on different websites and cant seem to find info about if they are chambered for 5.56 vs .223 . I would prefer 5.56. I have heard that you can fire 223 ammo in barrel chambered for 5.56 but not the other way around. I am in the process of building my first AR.

I guess it ultimately depends on what kind of rifle and for what purpose you are building it.  But for the most part if you just go 5.56, you won't have to worry.  You can fire .223 in a 5.56 and there is some arguement about the 5.56 in a .223.  This is a somewhat hottly debated topic.  I suggest you go to the ammunition forumn for further info, and if you haven't already, be absolutely sure to check out [url=www.ammo-oracle.com]ammo-oracle[/url] for the amswers to probably all your questions and maybe some you didn't have!


Hershey