.223 vs 5.56

[tmark]

With the smaller volume of the 5.56, I'd avoid max loads intended for .223 in the 5.56. Work up to max loads gradually and check for signs of excessive chamber pressures like flattened primer or punctured primers, hard extraction, etc.

[Parashooter]

I wonder if those of you asserting less volume for (military) 5.56 cases have actually checked the accuracy of that statement or are just repeating what you've seen on the internet. My own comparisons of Lake City cases and commercial .223 haven't shown any significant difference in weight or volume. While military 7.62 NATO cases are measurably heavier than most commercial .308 Win. cases, the distinction doesn't seem to hold for 5.56/.223 (or for .30/06 cases either). What have you found by actual test?

Also, my Lake City 5.56 case headstamps have only "LC", the year, and (in later years) the NATO standardization mark. They don't "say 5.56" as asserted in post #5 of this thread.

[Matt Anthony]

Is there really a difference and does it matter? I think so and this article explains it. However, one can do whatever they choose and shoot whatever they want in their firearms. The material to discern is out there and furthermore, one can call the manufacturer of theri firearm and find out what the gun should be fed. So much time wasted on this subject when the answers are so easily to get!
http://www.thetruthaboutguns.com/201...-5-56-and-223/

[Major Tom]

For many years I have fired both commercial and military ammo in my bolt and AR rifles. I have not ever had a problem. I'm talking 223/556, 308/762 and 30-06. I also reload, but, never max loads.

[browningautorifle]

I'm with Major Tom, this keeps coming up and all it does is argue. They both work fine in anything.

[dogtag]

Lake City brass is military, therefore 5.56
Other brass I have has 5,56 stamp.
Now, I really don't care what people shoot in their firearms,
as long as I'm not standing next to them.
I reload everything I shoot, and I use only my own cast bullets,
so 223/5,56 makes no difference to me.

[Matt Anthony]

Lake City brass is military, therefore 5.56
Other brass I have has 5,56 stamp.
Now, I really don't care what people shoot in their firearms,
as long as I'm not standing next to them.
I reload everything I shoot, and I use only my own cast bullets,
so 223/5,56 makes no difference to me.

As others have said, they shoot military rounds through their bolt guns without a hitch. The subject was, is there a difference between 223 and 5.56. The answer is YES, there is a difference, it cannot be disputed due to facts on chamber dimensions. Now, does it matter, it seems NOT, as I have never witnessed nor heard of a 223 bolt gun blowing up using 5.56 ammunition. It's not about brass, it's about the dimensions of the chambers and that's it! However, whatever is stamped on the barrel, that's what the manufacturer tooled the barrel for, so it's not hard to understand what to shoot in that rifle. I can't understand why there is any argument or even discussion on this subject. All one has to do is read about chamber dimensions and the discussion is over!
Matt

[tmark]

I was told by my gun store man that 5.56 can be fired in .223 bolt guns on a limited basis. Eventually, he said, the stress of the former round will weaken the bolt lugs and locking mechanism in the receiver.

Other sources say a 5.56 is not meant to be fired in .223 rifles. Google "Firing 5.56 ammo in a .223 rifle" for reliable data. The data says not a good idea to fire 5.56 in .223 rifles.

This should be a topic for mythbusters.

[Parashooter]

Wouldn't it be nice if everyone read the original post on this thread? In case you didn't, it's about brass for handloading - not about firing factory ammunition. Wake up, folks!

[Hefights]

Politics, religion, and 5.56 vs .223 (7.62 vs .308)