I’m sorry but I just remember you being very upset yesterday over an EMS referring to the casings at the scene as being 5.56 with posts like this:
“You aren’t suppose to use 556 in a 223 because of excessive pressure”
http://www.freerepublic.com/focus/news/2981821/posts?page=120#120
But I’m glad you cleared that up because it appears that a Bushmaster 223 can safely fire 5.56 ammunition so it wouldn’t be a surprise to find 5.56 brass at the scene, now would it???
She is correct, the wall thickness of the two cartridges are different.
The 5.56 case has thicker walls to handle higher pressures, meaning the interior volume of the case is smaller than that of a .223. This will alter the loading data used when reloading 5.56 brass to .223 specs.
Wrong again chippy....
http://www.humanevents.com/2011/02/15/223-remington-vs-556-nato-what-you-dont-know-could-hurt-you/