.223 and 5.56???

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DaveH14

DaveH14

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Newby to reloading. So I've read a few articles on these calibers. I've seen articles stating the cases are identical, another stating the 5.56 is a little longer (neck), there are no 5.56 dies and .223 dies can be used to reload the 5.56. So here we go, can I use a .223 case (PMC, LC, Winchester, Federal) to load up a 5.56 load using a small rifle CCI 41 primer? These primers are the only primers I can find right now. But my real concern is case length difference. Is this an issue? Thoughts.
 
not sure. I just load .223 Remington with .223 Remington dies. 5.56 brass is the same, just a touch thicker, but - if you are learning to load it, going anywhere near a max load and trying to get a 5.56 pressure and velocity is not anything I think anyone would advise anyone to do. never start near a max pressure, work up to it slowly if you're going to go there.
 
5.56 Nato and 223 Remington cases are identical.

The difference is in the chambers. The leade, I think that is what it is called, is longer in the 5.56 chamber. It is the reason it is not recommended to fire 5.56 ammunition in a 223 Rem chamber.

Unlike 308 Win and 7.62 Nato cases, 5.56 cases do not necessarily have heavier walls than the civilian 223 Rem cases.

Most military 5.56 cases will have crimped primers. The crimp needs to be removed before priming. Some civilian cases have crimped primers.

223 Remington dies will resize 5.56 cases just fine. You will not find 5.56 dies.

CCI 41 primers have a bit tougher cup to prevent slam fires in semi-auto rifles. They should work fine in your application. Treat them as magnum primers though.

Hope this helps.
 
DaveH14 said:
So here we go, can I use a .223 case (PMC, LC, Winchester, Federal) to load up a 5.56 load using a small rifle CCI 41 primer?
Click to expand...

Yes, you can. The 5.56 uses more powder at max load because it has a higher pressure limit than 223, all else being equal.
 
DaveH14 said:
Newby to reloading. So I've read a few articles on these calibers. I've seen articles stating the cases are identical, another stating the 5.56 is a little longer (neck)
Click to expand...
Dave, trust data published in reloading manuals first, and using two different manuals is a plus. Did the articles you mention cite the source for their information? My Speer and Hornady manuals show case dimensions of the .223 and 5.56 to be identical.
 
The brass is the same, the difference is in the chamber. The 5.56 has longer leads than the 223R and the 5.56 runs at a higher pressure. 62k vs 55k. As long as you follow load data for the round your loading you will be fine. With that said there is 1 223R Chamber that is designed to take the higher pressure, called Wydle.This particular has long leads like the 556 but at a sightly different angle. It was designed to shoot heavy bullets in the 223R.
 
film495 said:
not sure. I just load .223 Remington with .223 Remington dies. 5.56 brass is the same, just a touch thicker, but - if you are learning to load it, going anywhere near a max load and trying to get a 5.56 pressure and velocity is not anything I think anyone would advise anyone to do. never start near a max pressure, work up to it slowly if you're going to go there.
Click to expand...
Always, work up load......
 
Blue68f100 said:
The brass is the same, the difference is in the chamber. The 5.56 has longer leads than the 223R and the 5.56 runs at a higher pressure. 62k vs 55k.ri As long as you follow load data for the round your loading you will be fine. With that said there is 1 223R Chamber that is designed to take the higher pressure, called Wydle.This particular has long leads like the 556 but at a sightly different angle. It was designed to shoot heavy bullets in the 223R.
Click to expand...
My rifle barrel is chambered for 5.56 1-7 twist. If I'm reading this right my chamber will take both just fine. Loading up as recommended by the book.
 
I had a 223 under a 12 ga. If you fired 556 in it, it would be almost locked shut. Was very difficult to.open.
 
Here's everything you might want to know, OP.

https://www.luckygunner.com/labs/5-56-vs-223/

To my knowledge, the only commercial dies you'll find are labeled .223 Rem, and yes, you can shoot .223 ammo through a 5.56 gun. The dogma is you should not try it the other way around, and I'll just leave it at that. 5.56 has the longest leade (and thus the "loosest" chamber), while .223 Rem has a shorter leade ("tighter" chamber). Longer chambers can handle higher pressures and can better tolerate grit and gunk on a battlefield, while tighter chambers build (perhaps unwanted) higher pressures for a given cartridge and are more picky on cleanliness, but generally shoot more precisely, all else being equal. There's actually a spectrum of 5.56/.223 chamberings, for which the article provides a table. .223 Wylde, for example, is a popular hybrid of 5.56 and .223, and is intended for both cartridges. My AR Service (competition) rifle is chambered in .223 Compass Lake Engineering (CLE) Match, which is tighter than .223 Rem to try to squeeze every bit of precision out of a barrel.

There are going to be wall thickness differences between brass manufacturers, hence the same powder loads can generate different pressures with different brass. Keep that in mind if you're using random range brass to reload, as it would be best not to load everything near max charge. Also, military brass (and some commercial brass) is going to be crimped. You'll need to remove that so a fresh primer can be set in. I use Dillon's Super Swage tool, but there are other tools / methods. I also trim all my brass to 1.750" to maintain consistency. The CCI #41 primers you have are my favorite, if for no other reason than they are hard and minimize the potential for slam fires with the floating firing pin in ARs. (Yes, that's a thing and I've actually been present when a few occurred.) They also produce 5-shot, sub-MOA groups for my AR Service rifle. Beyond that, stick to your manual(s) and you should be alright. :)
 
.223 vs. 5,56 NATO

Although a little long this article is worth the read!

https://en.wikipedia.org/wiki/.223_Remington#.223_Remington_vs._5.56×45mm_NATO

Here's every thing you ever wanted to know about primers!

Primer Info & Chart + Milspec Primers for Semi-Autos & Other Primer Applications

Most AR15 style rifles are chambered for the 5.56 and marked as such and will accept the .223 Rem.

You may see bolt rifles and occasionally older AR marked .223 Rem. Use only .223 Rem ammo!

SAAMI web site: " it is not safe to shoot “5.56,” “5.56 NATO,” or “5.56x45mm” ammunition in a barrel marked as being chambered in 223 Remington for a number of reasons. The main reason being that a barrel marked as chambered in 223 Remington will have a shorter throat into the rifling than a “5.56” barrel which may cause increased pressure if the “5.56” ammunition is fired in it. This can result in serious injury or death to the user and/or bystanders, as well as damage to the firearm".

Reloading dies are found for .223 Rem and of course will also fire in 5.56 NATO chambers.

As mentioned above use load data from the manufacturers.

Sorry if I'm repeating the above post we were both posting about the same time!

Smiles,
 
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DaveH14 said:
My rifle barrel is chambered for 5.56 1-7 twist. If I'm reading this right my chamber will take both just fine. Loading up as recommended by the book.
Click to expand...

Correct.

If pushing loads near max, stick with one head stamp case and work up the load looking for pressure signs along the way.

223 Remington civilian cases can have less case volume than some military cases so it is best to work up loads for each separate case stamped case particularly if running near max.

If loading for a semi-auto rifle, I recommend using small base sizing die. It is just a bit of insurance against poor chambering particularly if you are loading for more than one rifle. I find no loss in case life using small base sizing dies.
 
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I load all .223 and 5.56 cases the same. There is variation in case wall thickness between different manufacturers but 5.56 cases are not always thicker than .223 cases or vice versa. I resize them all with the same .223 dies. You will want to trim them all to the same length or at least make sure they are within the spec length of 1.740 - 1.760. I trim mine to 1.752. But I only trim if the cases are over 1.755 and if they are under 1.745 I pitch them. You can reload down to 1.740 but I have so many I don't bother. The only difference you will have to take into account is that the once fired 5.56 cases have a military crimp that will have to be removed before you can reload them. When you are working up loads just make sure you are starting well within the published load data and then shoot from lowest load to highest checking for pressure signs as you go.
 
Gone Hiking said:
Here's everything you might want to know, OP.

https://www.luckygunner.com/labs/5-56-vs-223/

To my knowledge, the only commercial dies you'll find are labeled .223 Rem, and yes, you can shoot .223 ammo through a 5.56 gun. The dogma is you should not try it the other way around, and I'll just leave it at that. 5.56 has the longest leade (and thus the "loosest" chamber), while .223 Rem has a shorter leade ("tighter" chamber). Longer chambers can handle higher pressures and can better tolerate grit and gunk on a battlefield, while tighter chambers build (perhaps unwanted) higher pressures for a given cartridge and are more picky on cleanliness, but generally shoot more precisely, all else being equal. There's actually a spectrum of 5.56/.223 chamberings, for which the article provides a table. .223 Wylde, for example, is a popular hybrid of 5.56 and .223, and is intended for both cartridges. My AR Service (competition) rifle is chambered in .223 Compass Lake Engineering (CLE) Match, which is tighter than .223 Rem to try to squeeze every bit of precision out of a barrel.

There are going to be wall thickness differences between brass manufacturers, hence the same powder loads can generate different pressures with different brass. Keep that in mind if you're using random range brass to reload, as it would be best not to load everything near max charge. Also, military brass (and some commercial brass) is going to be crimped. You'll need to remove that so a fresh primer can be set in. I use Dillon's Super Swage tool, but there are other tools / methods. I also trim all my brass to 1.750" to maintain consistency. The CCI #41 primers you have are my favorite, if for no other reason than they are hard and minimize the potential for slam fires with the floating firing pin in ARs. (Yes, that's a thing and I've actually been present when a few occurred.) They also produce 5-shot, sub-MOA groups for my AR Service rifle. Beyond that, stick to your manual(s) and you should be alright. :)
Click to expand...
Yes, my rifle is 5.56 Nato and I do use range brass. I never have nor intend to shoot near max loads as recommended by Lee 2nd Edition. I swage any brass that looks like it had a crimped primer. Got lucky and was able to score 100+ casings of match grade brass at a CMP match this weekend. So much to learn. This is addicting........
 
DaveH14 said:
Newby to reloading. So I've read a few articles on these calibers. I've seen articles stating the cases are identical, another stating the 5.56 is a little longer (neck), there are no 5.56 dies and .223 dies can be used to reload the 5.56. So here we go, can I use a .223 case (PMC, LC, Winchester, Federal) to load up a 5.56 load using a small rifle CCI 41 primer? These primers are the only primers I can find right now. But my real concern is case length difference. Is this an issue? Thoughts.
Click to expand...

Unless you need the additional velocity of the .556 you can just use .223 data. That will give you plenty of leeway as far as pressure.

I use mixed .223/.556 brass in my loads, but I developed the loads using a single headstamp and .223 data.

I also run all my brass through the trimmer after sizing. If it needs trimming it gets trimmed, if it doesn't need it then nothing happens. Seems faster than trying to measure and separate every piece.

CCI 41 primers should work well. I started with CCI 450's and they work for me, but it was all I could find at the time.

chris
 
Skeptic13 said:
There is variation in case wall thickness between different manufacturers but 5.56 cases are not always thicker than .223 cases or vice versa.
Click to expand...
I'm betting the brass differences wouldn't be of much concern when loading for .223 Rem using 5.56 brass. However, it definitely makes a difference when cutting brass down for .300 AAC Blackout, which was my first introduction to .223/5.56 cases. I try to avoid tossing brass...so I spent over $150 on neck turning equipment so any appropriately shortened brass could be used in my 300 BLK loading. What I've experienced is that I've only had to neck turn 5.56 cases...I have yet to find .223 Rem brass that needed neck turning for my ARs.

Additionally, I haven't encountered any .223 Rem ammo (I built a couple .223 Wylde ARs to produce my own once-fired brass for conversion) that didn't have crimped primers..it seems more the rule than the exception.
 
I remove the crimp on everything. I've had too many 223 cases with crimped primers. I also load to 223 specs even though both my rifles are chambered for 5.56. I couldn't find data for 5.56 when I first started loading, so I just went with it. The Lyman manual doesn't have any, nor does Hodgdens web site. Ramshot has data for 5.56 with TAC, which is a powder I use but keep at 223 levels. Hornady also has 5.56 data but I haven't tried any of that either. I suppose I should, but my 223 loads shoot better than I expected anyway, so I haven't.
 
back when I first started reloading, .223 and 5.56 were the same cartridge, one was the civilian name the other the military name. Some time in the late 1980s that changed. The chamber in the 5.56 became longer, with
a longer and heavier bullet. Or at least that was my understanding. When you look at rifles today, they say one or the other, but generally the 5.56 will fire .223, but not the other way around. It is similar to the 7.62 mm round and the 308 winchester. Exterior size is the same, but 308 pressure is higher, and 7.62 brass is thicker. Or at least that is my understanding

course have to admit am an oldie kind of guy ha ha ha

as far as crimped primers, is my understanding and going back to military 30-06 in WWI AND WWII, military brass had a ring around the primer, that had to be removed before new primers could be inserted.
When the military went to first 7.62mm and then 223/5.56 that continued. but like I said am an oldie gent, and first military rifle I ever fired was the old M-1 Garand
 
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Most of my 223/5.56 loads are "223 loads". I just load what the gun likes.
I have one load that's full on 5.56, it's at the max load and that's just how it worked out and what the rifle likes, wouldn't recommend firing it in a 223 chamber gun.
 
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