5.56 vs .223 case gauge

[JWH321]

Is there such a thing as a 5.56 case gauge? I can't seem to find one. Most of the suppliers just say to use the .223 gauge. I'm finding some of my 5.56 rounds are a really tight fit in the .223 gauge but they drop into the chamber in the gun just fine.

I know this is picking nits, but I'd like to see the difference.

 

[JimKirk]

The same ... only the chamber of the gun is different ... Very similar to how Weatherby cartridges operate ... lots of freebore ... that allows slightly higher operating pressures over the .223 Rem ...

 

[JWH321]

Thanks Jim.