556 brass

markley

markley

New member
i have a bunch of 556 brass and i am buying a 223 rifle. i do reload. i have been reading online that the difference between the 556 and 223 is that the neck is a little longer and the brass itself is thicker so it can handle higher pressures. just trying to get a second opinion but if i trim the neck and resize them with 223 dies they should work in my gun? just wondering if there is anybody out there that does this.
 
I was just wondering because i am looking at getting a remington sps tactical 223. i see on some websites and dealer websites they have 223/556 next to it. but when i get on remingtons website it just says 223. so i am confused.
 
You will find a mixed review with strong opinions going both ways on this topic.
Some will say with ammo is interchangeable, some will say it is not.
If the rifle says 223/556 (or just 556) you can shoot both.
If it says 223, you should stick with 223.
My friend has a Savage rifle that says 223. He called Savage and they said he SHOULD NOT shoot 556 out of it. That is what Savage said.
Others will say you can, but they are not the makers of the rifle.
A lot has to do with manufacturers liability I'm guessing.

Your original question was can you reload your 556 brass. Yes. Prep your 556 brass like you would your 223 brass, use a 223 recipe, start low and work up and you will be fine. I actually have more 556 brass than I do 223 brass and have never had a problem.

Did you read those links? Lots of opinions and information in there.
 
Weigh a few of each case. I've never found any 5.56/.223 cases to be more than a couple of grains different. I use the same "recipe" in both of them without any problems, but I didn't develop it to be a max charge, so I have a decent safety zone.

I found that the "5.56 brass is heavier" to be a myth. If you get any 7.62 NATO/.308 brass, though, be careful, because the 7.62 is usually a LOT heavier.
 
Originally Posted By: markleyi have a bunch of 556 brass and i am buying a 223 rifle. i do reload. i have been reading online that the difference between the 556 and 223 is that the neck is a little longer and the brass itself is thicker so it can handle higher pressures. just trying to get a second opinion but if i trim the neck and resize them with 223 dies they should work in my gun? just wondering if there is anybody out there that does this.

If the "brass is thicker so it can handle higher pressures" ... and you make the outside the same diameter as a .223 Winchester, then what happens to the inside? It will get SMALLER, of course. And if it DOES get smaller, it had darn well better be able to handle higher pressures.
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Now, I'm not saying that is what will happen, and I'm not saying whether you can load them safely, but I would use a great deal of caution when selecting a starting load. Start with the lowest pressure load that you can find published, and work up VERY slowly.

Reloading is essentially like baking a cake. You use known ingredients in exacting amounts. In the case of this brass you are about to use, you are not certain of the internal capacity. That is an UNKNOWN ingredient. Be careful and go slowly.
 
I am guessing the brass you have is military surplus. If that is what you have, just make sure you clean the crimp off the primer pocket. Other than that, Full length resize and trim to length the first time so it will fit the Rem chamber easily. I have the .223 SPS Tactical and shoot .223 and 5.56 interchangeably. Just not at the same time. Not that any danger exist. It's just that doing so is akin to shooting different lots of ammo/powder/primers ect. at the same time. Accuracy suffers.
 
The brass is the same(except for the crimp) for both rounds. Where the difference lies is how the ammo is loaded. The 556 chamber is throated longer, and 556 ammunition is loaded to a higher psi(i think it is 62,000K but I am not sure). The brass itself is the same though. In fact 223 lapua brass tends to be thinker then LC brass
 
Gee I wonder why it is then all the .223 Rem cases I've fired all spec'd out to 1.740-50" while all the 5.56mm spec'd out at 1.760-70" Could it actually be that the .223 case Spec is "wait for it" is 1.750" vs a case spec of 1.760 for 5.56mm!!! Could it also be the Chamber spec for .223 is Max 55,000 psi vs the Mil spec for 5.56mm is 62,000 psi! Or do all you guys run your handloads over spec? Sure you might get by firing 5.56mm in your tight .223 Rem chamber but the question is how long and do you like your eyes! Maybe you all dream of being blind one day not this shooter! And yes there have been AR's blown up! Do a search! Lets see SAAMI say not too, Gun Manufactors say not too, so why would you? If it's not a problem then why wouldn't the Military not chamber there M4's to .223 Rem for more accuracy and cheaper ammo?
 
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If you resize and trim a 5.56 case to .223 size, how is it causing higher pressures?

I'm not saying to shoot a factory loaded 5.56 out of a .223 chamber, that is inadvisable. But once you resize it to .223 spec and then reload it to .223 spec...what are you worried about exactly?
 
Resize a few of each with the 223 dies and trim the crimp on the 556. Trim them all to the same length. Weigh each of them. The heavier ones will have less capacity for powder. If they all weigh the same, nothing to worry about.
 
You are posting SAAMI pressures that are at least 20 years old. Not that way today.
Look at the latest reloading manuals that show higher loads for bolt guns in 223 than for AR's in 5.56.

Jack
 
Jack Roberts
But we are talking AR, not bolt gun! Yes you can trim 5.56mm to the .223 Rem Spec and use them in a .223 Rem chamber! I do just the opposite and let my .223 Rem brass grow to 5.56 mm spec before they get trimmed! As both my AR's are 5.56 mm chambers -why would I own a .223 Rem chmbered AR -kind of dumb!
 
Quote:...why would I own a .223 Rem chmbered AR -kind of dumb!


That's all you'll find a match barrel chambered for?
Why would I want my hunting rifle chambered for 5.56? It's all FMJ.
 
You can reload 5.56 brass to use in a .223.

I do not recommend shooting Mil Spec 5.56 in a .223 chamber. As posted above they are loaded to a higher pressure. Blew primer in a M700 doing the above.

Once fired brass can easily be used. Just work up a load for your individual rifle.

Good luck

Jerry
 
Hey thanks. Took out my new rifle today and just shot some cheap remington pmc through it and my last 5 shot group was just a little over an inch. So i cant wait to see how my handloads do.
 
Trim specs are the same for both. the only concern there ever was was
the higher pressures of the mil. spec ammo stretching the case neck into
the freebore of the 223 and pinching the bullet. We used to have what was
referred to as the broken bolt club. Winchester had a warning and explanation on their website for years.
 
bigwheeler
Really?
Trim lenghts in manuals: for Rem .223

Barnes #3 Manual- trim to 1.175" Obviously a typo!!
Lyman Cast Bullet Handbook 1.750"
Load books 1.750"
Speers #13 1.750"
Nosler #5 doesn't give a trim to Lenght!

You have to go to Army ordinance Spec sheet for 5.56mm and I have case lenght is 1.760" Other wise brass is the same as commercial brass as for spec!
 


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