Problems loading 5.56

[jeepster11]

alright now i have some 5.56 and i have 223 dies can i load these with 223 dies or buy the 5.56 dies i know the 556 has thicker walls and such for the 556 any pointers that will make it easier to load these would be appreciated.

i load .308s and have no probems why are 223s so dificult to load the .308s are easy.

[fpchief]

.223 dies, and use case lube. Don't use the spray on type like one shot.

[Jim243]

Have yet to see any 5.56 dies, last time I called Lee they said they can make them up, not that expensive but everything is on backorder for 6 months.

If you know of any for sale, let me know??

Jim

[Clark]

Weigh the 223 commercial brass and weigh the 5.56 military brass.
The are the same or commercial is a little heavier.

It is not like 308 brass, where the 7.62x51mm Nato brass is heavier.

[riverwalker76]

We should all pool our resources and see if Lee will do a limited production run of 5.56 dies.

No joke.

I'll call them tomorrow, and see what needs to be done to get ... let's say ... 1k of them made up in a day. They'll already have the tooling set up for it ... might as well make use of it.

Do you all agree or not?

[rjrivero]

I don't understand why you would want to load 5.56. I mean, any "uber accurate" rifle will already be chambered in .223. All .223 ammo will run in 5.56 chambered guns already. 5.56 pressures will be rather tough to contain without crimping the primer in place to keep the primer from freeing itself and mucking up the works.

Even if I could crimp the primers in place, I'm not sure I'd want to swage the brass every relaod if I could help it.

So, my question is this: Even if the 5.56 dies were readily available, why would I want them?

[riverwalker76]

I don't understand why you would want to load 5.56. I mean, any "uber accurate" rifle will already be chambered in .223. All .223 ammo will run in 5.56 chambered guns already. 5.56 pressures will be rather tough to contain without crimping the primer in place to keep the primer from freeing itself and mucking up the works.

Even if I could crimp the primers in place, I'm not sure I'd want to swage the brass every relaod if I could help it.

So, my question is this: Even if the 5.56 dies were readily available, why would I want them?

You are misinformed concerning the reasoning behind the primer crimp. It's because of the battle fatigue placed on the cartridges during transport. I've seen guys throwing ammo cans 10 feet into a Blackhawk just so they could hurry up and resupply the front line. Then ... I've seen the rear gunner throw the ammo cans out the door and hit the ground while hovering at 6 feet above the AirHead.

I shoot the 5.56 because that's what my AR15 is chambered for. Sure I shoot .223 on occasion, but why when you can buy 1k once fired military brass for 1/10th of the cost of .223 new?

Every AR15 owner that I know prefers 5.56 over .223. Honestly, it's probably a cost factor. That's also considering that a lot of us throw 3k+ rounds down the pipe in a year.

Figure the cost in .223 for the same usage, and you will be breaking the bank.

That's why I LOVE 5.56 NATO.

[jeepster11]

i have a bushmaster e2s and i love it its capable of shooting either 223 or 556
now if i have 556 brass is it a little harder to load it? its once fired and not crimped by the primer i believe its lc brass mainly but i have remington and winchester and american eagle and some other brass will these all load different should i seperate them by brand thanks shane all of your info is appreciated

[riverwalker76]

I separate all of my 5.56 and .223, but don't worry about makers or brand in these respective categories.

In other words ... I have .223 in Remington, Hornady, Winchester, and PMC.

In 5.56 I have Lake City, WCC, and other mixed headstamps.

In my experience the 5.56 doesn't take as much of a charge to reach the same pressures as the 223. So, if I use a charge of 21.2 grains in .223 I might have a charge of 21. grains in 5.56 to reach the same velocities.

[Clark]

riverwalker76
Senior Member

Join Date: February 13, 2010
Location: Owensboro, KY
Posts: 510

Quote:
I don't understand why you would want to load 5.56. I mean, any "uber accurate" rifle will already be chambered in .223. All .223 ammo will run in 5.56 chambered guns already. 5.56 pressures will be rather tough to contain without crimping the primer in place to keep the primer from freeing itself and mucking up the works.

Even if I could crimp the primers in place, I'm not sure I'd want to swage the brass every relaod if I could help it.

So, my question is this: Even if the 5.56 dies were readily available, why would I want them?

You are misinformed concerning the reasoning behind the primer crimp. It's because of the battle fatigue placed on the cartridges during transport. I've seen guys throwing ammo cans 10 feet into a Blackhawk just so they could hurry up and resupply the front line. Then ... I've seen the rear gunner throw the ammo cans out the door and hit the ground while hovering at 6 feet above the AirHead.

CAUTION: The following post includes loading data beyond currently published maximums for this cartridge. USE AT YOUR OWN RISK. Neither the writer, The Firing Line, nor the staff of TFL assume any liability for any damage or injury resulting from use of this information.

There are lots of reasons for or against doing anything.

I was shooting some hot 25acp loads this week. Some REALLY hot 25acp loads.
I had an unusual jam. One 25acp pistol would not come off safety. I disassembled and found that one of my primers fell out of the primer pocket when the primer pocket expanded due to high pressure. see pic of primer stuck in 25acp pistol.

I have found the 25acp case head to be weak, with little brass between the extractor groove and the primer pocket.
In contrast, I find that the .223 case head to be strong, and loads that Quickload thinks are 75,000 psi will still have long brass life. Loads that Quickload thinks are 90,000 psi cause the primer pocket of .223 brass to expand and fall out. see pic of 223 brass with fallen primers.

[CJ7365]

Not sure I understand the difference between .223 dies and 5.56 dies, I have been loading, once fired LC brass using Lee Pacesetter .223 dies, over 1500 rounds with no problems, am I doing something dangerous, wrong can someone please explain the difference in using a .223 verses a 5.56 die, I have not even see a 5.56 die for sale.

thanks

[dlb435]

There is no point in either making or getting 5.56 dies. The 223 dies are almost identical.
5.56 NATO specs call for heavier brass wall than does 223. I did some testing a few years back and found that while 5.56 brass was heavier than 223 brass on average, some 223 brass was the same or even heavier than 5.56 brass. The same went for interior case volume. On average, the 5.56 is a tiny bit smaller but some 223 brass is also smaller.
Does this make any differance? Not really. I loaded a bunch of rounds with the different cases and chronoed the results. There was no significant variation.
What NATO specs call for is for the barrels to be able to handle some 10,000 psi higher chamber pressures than 223 barrels. This does not mean that all NATO 5.56 rounds are loaded to that higher pressure; it just means that the barrels can take the higher pressure. Using 5.56 rounds in a 223 barrel COULD damage your gun.
NATO specs also call for a few extra steps in the ammo that are not called for with 223 ammo. Little things like crimped primes, sealant around the primer and the edge of the bullet. All this goes to making the ammo as reliable as possible in the field.
Is there any reason to reload to NATO specs? None that I can see. I sure don't need sealed crimped primers and sealing around the bullet. Loading to the edge of the NATO pressure specs could be dangerous, so I wouldn't do that either. If I need more power, I could just step up to a 243 or similar cartridge.

[Jim243]

DLB435

I would beg to disagree with your observation. I would be happier to use 5.56 dies on 5.56 cases than the standard 223 dies.

First, thousand of 5.56 dies are made for LC, Winchester and anyone else that maufactures ammo for the DOD. Strangely none are aviable for civilians?

The major difference is in the sholder of the case. If this makes a difference by sealling the case better to the chamber and insuring that all gas and energy goes down the barrel and provides a better fit to the chamber by the case, I would certainly prefer that.

Jim

[Unclenick]

This is much ado about nothing. The 5.56×45 is the NATO-ized version of the .223. The differences are in the chambers (see attached reamer spec comparison from AR15barrels.com). They are not, however, in the external brass dimensions. That is because the .223 was developed for the military. It was merely commercialized as .223 Remington, and is not a case of a commercial load being adapted to military use.

The military chambers are more generous to accommodate specialty ammo and ensure full-auto feeding. This means once-fired military brass is typically blown out larger than the exact same ammo would be if once-fired in a SAAMI spec chamber. Brass is springy and is not returned 100% to original size by a resizing die. By how much it fails to return to size depends what size was when it went into the die? Indeed, as Sierra's manual points out, some brass can be stretched so extremely that it simply cannot be made to fit a smaller chamber by using any standard sizing die; not even a small base die. We've had that situation that pop up in a few threads here.

5.56×45 and .223 drawings from QuickLOAD. I'll let you pick out which is which?



The above explains why .223 and 5.56×45 new cases both fit each others chambers. It explains why the same sizing dies work for both if the cases are fired for the first time in the same chamber. It explains why small base .223 dies usually cure problems with resizing once-fired brass that has been stretched excessively in a NATO spec chamber, not to mention stretched by extraction in a machine gun. Frankly, I don't know how a 5.56 die set would be any different from a .223 die set unless small base .223 sizing dies would be its default? Lee doesn't currently make a small base .223 sizing die, so maybe that's what they had in mind for a custom set?

A 5.56×45 chamber has a longer throat, but it's only 0.025" longer than the standard .223 chamber. I don't believe I've ever seen a .223 seater die that couldn't be adjusted for that 0.025" of extra length a NATO throat has, so that part of a 5.56 die set should be no different.

Then there is the pressure issue. I don't really believe it. Take a look at the top group of cartridges in the table below. These are cartridges that, like the .223, were originally specified by SAAMI at 52,000 CUP Maximum Average Pressure (MAP) for ten rounds of a test load fired in a test gun. Now look at the newer PSI MAP specs for them in the second column. The new specs for those cartridges average 62,000 PSI. Next look at the .223's new spec in PSI. See how much smaller the difference is than for the others? I don't know if that is the result of the anomalous behavior of the two measurement systems or if the pressure spec was reduced by SAAMI between the changes? I suspect the former, but have no solid way to tell without asking SAAMI? CUP by copper crusher and PSI by non-conformal piezo transducer have a pretty shaky relationship.

Now go one step further and look at the CIP specs for the two rounds at the bottom. Their conversion from old CUP standards to new PSI standards is much closer to what you'd expect to see based on the SAAMI average conversion for other 52,000 CUP cartridges. The CIP locates their pressure test ports differently, and perhaps that corrects the difference issue for their copper crusher and piezo transducer readings?

So, I believe this pressure issue is mostly created by the anomalous nature of the measuring systems. CIP pressure port location is known to read about 2,000 psi (not 20,000 psi, as some claim) higher than SAAMI port locations with the same transducer type. That is likely why the CIP crusher number is about 1,700 CUP higher than the SAAMI crusher number, though that would be an unusually tight tracking of different crusher numbers if it were. Certainly the European NATO countries are using the European piezo transducer arrangement to load NATO ammo. But since we developed the cartridge and provided them with the reference loads, I expect it is just how the same ammo reads in their gear. So it probably reads 52,000 CUP on SAAMI's gear where it reads 53,664 CUP on theirs.

So, we have very close agreement between SAAMI and CIP CUP standards. We have the fact we sent them the round to copy, not the other way around. We have the fact that the SAAMI PSI MAP is so much lower than those for other cartridges they have converted the standard for from the same CUP MAP numbers that it is likely one of the anomalous scatter points that appear using these measuring method. Taken together, it suggests the 5.56 NATO pressure difference is more instrumentation artifact than real.

The one remaining pressure difference that may be legitimately disguised by all those differing pressure readings seems to me to be that NATO pressure tests are run in a NATO chamber with its longer throat and bigger diameter at the base, while SAAMI's are done with the shorter throat. That will be an issue if you try to shoot NATO specialty ammo with an ogive far forward enough in the chamber to get close to or touch the SAAMI throat. But if you are talking about ball ammo, the difference is unlikely to be much. Certainly the .223 Match chamber put in my AR by Compass Lake has never had any issue with surplus ball ammo, which it digests just as well as anything else.

There has been enough surplus 5.56 sold and fired in SAAMI spec rifles that if gun damage were a normal outcome, we'd all know about it. Not to mention that rifles chambered for .308 and other 60KPSI+ American chamberings are also chambered in .223. The guns can clearly take the higher pressure. Only the brass has the potential to be a weak link.

SAAMI MAP specs for various cartridges:

52,000 CUP	60,000 PSI	243 win 
52,000 CUP	60,000 PSI	308 win 
52,000 CUP	61,000 PSI	7mm SE vH 
52,000 CUP	61,000 PSI	7x50 R 
52,000 CUP	65,000 PSI	270 win 
52,000 CUP	65,000 PSI	6mm rem 

52,000 CUP	62,000 PSI	Average of all above 

SAAMI MAP spec for .223:
52,000 CUP	55,000 PSI	223 rem 


CIP MAP spec for .223:
3,700 bar(crusher)	 4,300 bar (piezo)	223 rem 
conversion:
53,664 CUP	62,336 PSI	223 rem

For the OP: Note the chamber differences do make brass once fired in NATO chambers sometimes hard to resize for use in SAAMI chambers. Buy a small base die and use it at least the first time you resize it. That fixes the problem most of the time, though not always. Get a case gauge and use that to sort out what the small base die has correct fixed and what it has not. Try re-resizing the oversize stuff in the small base dies, leaving it pressed into the die for a count of five. Do that twice. It often gets the last couple of thousands of interference out.

Once you have fired the brass in your gun's own chamber, it likely will resize fine with a standard die, but again, not always. If not, continue using the small base die if the brass seems to be OK otherwise. If it shows pressure signs, though, even with fairly moderate starting loads, it has likely been permanently damaged by over-stretching. We had a fellow recently whose once-fired .308 brass stuck in chambers even when loaded significantly below listed manual starting loads. At the same time, new Lake City or IMI brass gave him no problems with loads above the same manual starting load level.

[dlb435]

Thanks Unclenick, I think that says it all.

[greco]

UnkleNick... this is probably the best writeup I've ever seen regarding the 223/5.56 issue. Thanks for taking the time...

[Tim R]

Unclenick......so which drawing is which?

I shoot High Power with a WOP AR upper. If any of you think I would be loading anything which would hurt a upper you are wrong. My Dies are all marked 223. I like L/C brass. I will not shoot any Fed. 223 brass.

[riverwalker76]

I was going to add this a day or so ago, but I lost the post ....

First ... Thanks UNCLENICK for putting to rest these Urban Legends we all come up with.


Lee doesn't offer a small base die for one reason alone. Most 5.56 chambered firearms are slightly oversized at the chamber anyway. This is because the manufacturer has forseen issues in the past with firing reloaded LC brass in our 5.56 chambered ARs, and have fixed the problem for the consumer. Lee Full Length sizing dies are sufficient for reloading any once fired LC brass or equivalent.

Lee goes as far as to say that if you have a problem with resizing your 5.56 milsurp brass using the .223 Lee Full Length Sizing die ... send it back to them with 3 of the casings, and they will adjust your die for the brass.

Now you know why I love Lee products so much. They are usually a step ahead of us, and don't charge the exorbitant prices other companies charge.


The only way I would be able to justify buying a small base die set would be if I was shooting match .223 using LC brass out of a bolt rifle.

[Unclenick]

TimR,

The left one with the radius detail is from the .223 file.

[demigod]

delete - wrong thread.

[Lavid2002]

5.56 pressures will be rather tough to contain without crimping the primer in place to keep the primer from freeing itself and mucking up the works.

What?......

The primer doesn't fly out of the casing. Military brass is crimped to prevent a primer from coming out and jamming up the rifle. Its a reliability thing. When something is protecting you and your fellow soldiers lives, its gotta work.


As for the range. VERY rarely does a primer come out of the casing. When excessive pressure are reached the primer is indeed pushed back from the casing, but remember the bolt face is there. The primer is flattened against the bolt face, the pressure is vented into the atmosphere, then the casing is chucked out of the rifle, spent primer and all.

[demigod]

Indeed! The notion that you need a crimped primer when pushing 5.56 velocities/pressure is absurd.

[rude robert]

Very nice write up, is there a link where I can copy that?

not sure why people are against the small base die, but I am new to the ar's. I received my sb dies yesterday and all my extraction problems with away.

[greco]

I have SB dies for 223 and .308. Seems to make things work better.

[Unclenick]

The main aversion comes from small base dies working the brass more which shortens shortens case life. A lesser consideration is that the looser the cartridge sits in the chamber, the less perfectly it centers the bullet in the chamber. If you make case measurements, you'll find the small base dies come closer to returning the brass to its original dimensions than a standard sizing does. A standard die usually gets it somewhere in between that and the size it came out of the chamber at. That's a difference you can see on the target in guns shooting sub-1/2 moa, but not usually before you are in that precision range.

Some guns do seem to feed better if their brass has been resized with an SB die, while others don't. I suspect this is a matter of extra stretch of the brass at firing due either to a rough chamber or to overly energetic extraction. My AR has a tight match chamber, but feeds conventionally resized cases just fine.