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How to differentiate Lake City 223/556 Brass

An experienced shooter suggested that you should sort by weight. I sorted about 100 pieces and found about a 3 grain spread. About 2/3 were within 1 grain spread ( 92 - 93 grain). have not had a chance to shoot the segregated middle spread.
When I've sorted LC brass, I've had about the same results. There were very few at the extreme low/high weights.
 
Wait - what is the difference between Lake City '223' vs '556' brass? The dimensions of the brass is the same, yes? Does Lake City make some brass with less brass in the head/web or with softer brass?
 
My understanding is the difference between the LC in the 5.56 and the .223 marked cases is the higher pressure loading of the 5.56, as the military does. That is why the warning to not fire 5.56 loaded ammo in a standard .223 chamber, even though the dimensions, of the brass, are the same. The higher pressure loading of the 5.56 is not a good for continued firing in a standard .223
chamber.
 
The pressure differential isn’t that severe. Much of the concern is due to the differences in the chamber.

https://ballistictools.com/articles/5.56-vs-.223-myths-and-facts.php

all that said...AFAIK, Lake City only produced brass cases suitable for 5,56 mm rifles. It doesn’t matter what the headstamp says. The FC case above was made at Lake City when Federal ran it. They made “Federal” cases using Lake City equipment. There is NO REASON to assume that the cases are different than normal LC production (5.56mm).
 
So if does not say .223 on it, It’s 556?

OP are you confused enough now?
So it looks like its 556 unless marked 223.
I had no doubt it was out there just don't remember seeing.
556 is loaded hotter, chamber is more roomy.
This thread is a good one!
 
If LC ammo that is not marked 223 Rem (so it is 556) is fired in a 223 AR 15,Is the fired bass then equivalent to LC 223?
 
If you shoot a 223 in a 5.56 chamber will the bullet even make it out of the barrel?

Ask Quickload, it will give you pressure and velocity for both throat lengths.

If a deaf man fires a .223 in a AR15 rifle in the forest does it still make a sound?

Come to think about it, my speedometer is marked in mph and kph. So do I go with the decimal or metric speed?
 
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Remember. The question is about the brass, not the chamber.
Even if there were some dimensional difference in brass, wouldn't it be fire formed to your chamber after it's fired?
 
The basic difference between Lake City 5.56 brass and .223 is the Lake City cases are made of harder brass. And the majority of .223/5.56 cases have about the same capacity.

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Both the .223 and the Lake City M193 ammunition are loaded to 55,000 psi. The problem is when the 5.56 ammo is fired in the shorter .223 throat the chamber pressure will go up approximatly 5,000 psi.

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And the throat in my Savage .223 with a 1in9 twist is longer than my AR15 rifles.

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Are there 5.56 specific reloading dies?

After you size the brass, does it really matter how it was originally packaged?
 
I purchased the the 5.56 barrel so I can shoot either 223 or 5.56 instead of the wild no issues..dies r 223
 
Are there 5.56 specific reloading dies?

After you size the brass, does it really matter how it was originally packaged?

5.56 is the European metric equivalent of the decimal .223. If you look at your speedometer it has mph and kph and the needle points to the same speed.

Are there 5.56 specific reloading dies?

The black RCBS die box below is labeled .223/5.56x45. Meaning there is no difference in the dies.

The good old 30-06 metric designation is 7.62×63mm and we use 30-06 dies.

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