Just for fun I'll tell you what I tell the truckers that come through the plant and don't want to follow proceedures because "I've been doing it this way for years".
Just because you've been doing it for years doesn't mean you've been doing it right for years.
Oh how I've missed our banter. Where have you been hiding?
I don't really see what the difference is since almost all ammo I find in the local shops is marked .223 which no matter how you look at it is safe in any of the 223/556 and variant chambers. Other than the junk Norc stuff there isn't that much 5.56 ammo available around here unless you go out looking for it (yes you can find it but 223 is way more common).
The only rifle I own that actually has a .223 chamber is my Remington 700 and there is no reason to ever waste barrel life shooting bulk junk through that one.
As stated, the difference is minute, and on a service grade rifle who cares. If you're into F class shooting you might not want to run 5.56 through your gun. Then again, if you're into the extreme accuracy game you aren't running factory ammo anyway so its a moot point. Many a shooter has run mil spec ammo in civvie chambered rifles without issue. Feel free to do otherwise, but the reality is that nothing catastrophic will happen.
TDC
