223 cases

Is there any difference in case dimensions of the 223 vs: the 5.56? My AR's are chambered for 5.56 and my bolt action is chambered fore 223. Are there diferent dies for the two or can 223 dies be used for 5.56?

No differance!
Same exact thing.

There are only .223 dies made and they are used to load both.

The only difference in cases is GI brass is sometimes, but not always, slightly heavier, which gives slightly less internal volume.

That means a max load developed in .223 cases may be an overload in 5.56 cases.

rcmodel

One thing I've noticed on the 5.56. Specifically Winchester Q3131. There is a slight crimp at the case end at the cannelure. I don't reload, but I can imagine it would be something to be aware of.

The case mouth crimp is ironed out by resizing when the expander ball is pulled back out of the case neck.

Then all once-fired cases should be de-burred inside & out with a deburring tool.

When all that has been done, the slight case mouth crimp is history.

rcmodel

Cool.

http://www.6mmbr.com/223Rem.html