223 Remington vs 5.56x45mm reloading help

[mtls44555]

Hello, I am new to reloading my own rounds and I have this book that gives me all of the information on how to do so. It does not how ever tell me the measurements the 5.56x45mm, can i use the 223 Remington measurements ? Are they the exact same and is it safe to use that type of ammo in my (Stag)AR-15?
Any help would be appreciated.

[BlackEagle]

Welcome to the forum, mtls. You're sure to find lots of help here. There are some real experts here who will be more than glad to help. Enjoy the rest of the forum, while you're here.

[Conman]

Here you go. No sense re-inventing the wheel.

http://www.ar15armory.com/forums/556...Ch-t22582.html

[JLA]

Only difference is 5.56X45 rifles have a longer leade and are proofed for higher pressures.

Yes you can use the .223 dies and measurements to load 5.56X45

[JLA]

BTW, Im gonna move this thread to ammo and reloading.

[steve4102]

Originally Posted by mtls44555

Hello, I am new to reloading my own rounds and I have this book that gives me all of the information on how to do so. It does not how ever tell me the measurements the 5.56x45mm, can i use the 223 Remington measurements ? Are they the exact same and is it safe to use that type of ammo in my (Stag)AR-15?
Any help would be appreciated.

First, welcome!

Second, what do you mean by "measurements" ?

The 223 Rem and the 5.56 are identical as far as the handloader is concerned, only the lead/throat in the rifle chambers differ. You use 223 dies and 223 loading data.

[mikld]

This comes up often enough to become a sticky. How about it JLA?

I first ran into this "problem" a bunch of years ago, when I was shooting 5.56 surplus in my .223 Handi Rifle. I got pierced primers with 5.56 ammo (mebbe 4-5 out of 20), but not so with factory .223, 50 grain SP. I believe it was 55 grain FMJ, which is on the edge for stability with a 1-12" barrel...

[American Leader]

Welcome aboard mtls44555 from the "GREAT STATE OF IOWA"!

[JLA]

Ill stick it if it helps.

[OldFotoMan]

Aside from what has been said already, and to help clarify it; There were 2 different 5.56 loads and a 223 load. The 2 5.56 cases are the same, but loading data is different for the M193 and the SS109 rounds due to the 1 in 12 twist for the original 193 and the 223 and the 1 in 7 twist of the SS109. The main difference in the cases is that the 5.56 brass is thicker, and so uses less powder to create the same pressures. So if you're loading 223 brass, you can certainly use 5.56 loading data and work up from there for hotter loads. But if you're loading 5.56 brass, using 223 data will create too hot of a load to begin with. Stick with the data for the 5.56 to begin loading that brass. Also, check the gun you're going to use them in to see what the rifling twist is, and start with the proper loads for that twist no matter which cases you are loading. In short, to be safe, always start with the lowest charge or weakest load, then work up for what is safe in your gun. What's safe in one may not be safe in another. Know your gun and match your loads to it. This takes trial and error, or advise from someone else loading for the same gun is always a great help. Cartridges of The World is a good reference (it gives you all of the measurements you'll need) to give you some factory and hand loading data that has been tested, and there are many other good reference books for hand loading available also.

[dammitman]

so, does all this mean that all the high pressure was all due to the "leade" of the barrel and not to any of the load data unless one takes into account the "tiny" amount of space that is taken up by the thicker case of a 5.56 military case that isnt manufactured into a 223 case? and would all this high pressure concern be easily dismissed as long as any round would fit into a factory magazine whether military or civilian because that would eliminate the concern of "leade"? only "so long" a round will fit into a magazine and function, and its pretty short.

[BlackEagle]

dammitman,
The rule of thumb I learned and seems to work OK for me is to use 10% reduced charge for military brass. So, if the data book calls 25 grains of powder a maximum, (for a conventional case) use 22.5 as a maximum charge for military cases.

I find that maximum loads for conventional cases can fill a military case too full.

[dammitman]

that really sounds like good info and advise, i want to load some of that new CFE223 hodgdon powder and seem to have boatloads of military brass but alas no info directly for military brass but will just decrease the start by 10% as suggested. then cronograph and inspect fired brass as well as check overall accuracy of actual shots. i genuinely enjoy working up specific loads using same bullets, powder, primers and brass made to be specifically for one specific gun to be the perfect, most accurate developed round for that gun, then make buttloads of it!!!

[cpttango30]

For the most part Mil brass for the 556/223 is not very different.

Before you all start blasting away. Read the 6mmbr.com article about 223/ 5.56.

http://www.6mmbr.com/223rem.html

[BlackEagle]

Great link, Tango;
I saw that site some time ago, and it is well worth the re-read.
Thanks for the reminder.

[graehaven]

Just read an excellent article on the whole 5.56 and .223 debate:


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

[steve4102]

Before you go and arbitrarily reduce charges by XX% because of something you read on the internet, you need to check a few things.

The first is the link posted by CPT. In this article you will see that in fact the 5.56 Military brass has MORE case capacity than 223 Civilian brass.

More case capacity coupled with a 10% reduction in "Start" charge is a recipe for disaster. Do NOT DO IT!

Here is a good article by Sierra on the subject.

The conventional wisdom to reduce loads with military brass is familiar to most reloaders and is generally good advice. The rationale here is that the military cases tend to be somewhat thicker and heavier than their civilian counterparts, which in turn reduces capacity and raises pressures. This additional pressure normally requires a one or two grain reduction from the loads shown in most manuals or other data developed with commercial cases. While this is most often the situation with both 308 Winchester and 30-06 cases, it is less true with the 223 brass. We have found that military cases often have significantly more capacity than several brands of commercial brass. Again, take the time to do a side-by-side comparison of the cases you are working with and adjust your load as needed. There may be no need for such a reduction with the 223. Know your components and keep them segregated accordingly.

Link
http://www.exteriorballistics.com/re...sgunreload.cfm

[steve4102]

The main difference in the cases is that the 5.56 brass is thicker, and so uses less powder to create the same pressures. So if you're loading 223 brass, you can certainly use 5.56 loading data and work up from there for hotter loads. But if you're loading 5.56 brass, using 223 data will create too hot of a load to begin with. Stick with the data for the 5.56 to begin loading that brass.

This is all wrong. Beside the fact that you have the case capacity backwards, 5.56 load data runs at a higher pressure than 223 data. 5.56 data is few and far between, but it is available from Western Powders. Their 5.56 data runs at 62K psi while their 223 data runs at 55K psi.

Starting out with 62K 5.56 data in a 223 case(less capacity) in a 223 chambered rifle may not be such a good idea. Best to load for the specific chamber instead of the brass headstamp. Then you can determine case capacity and if you need to adjust accordingly.

[time2shoot]

One thing everyone has not said is, powder type.
You allso need to know where the burn rate is at for the powder you intend to use.
That alone can cause majer presher diffrences.

I'll use my 300 winmag. for an example: I reload 150 gr green tip. on top of 71gr. of H414. now this is around 90% case capasaty. and does not couse any over presher ishues.
I started out loading 67.5 grns. at around 85% capacaty. was saposed to be the most acuret load for this combo. this load was cousing pierced primers and split brass necks.
Do to the burn rate of H414. it would couse extr presher do to the empty volume of space. So once again we get back to case cap.
So all in all you need to take into consideration not only case Cap.but burn rate of your powder being used aswell.
This is just my opinion on what I have exp. While reloading do to trial and errer.
Hope this helps thoughs wondering.

[dodge]

ok now that i'm totally confused, my son got me a bunch of brass from his work as a security guard, after they shot. the boxes say 5.56 77 gr. sierra hp made by black hills ammunition. he wants me to reload them for his ar-15 which the barrel says will shoot either .223 or 5.56. i would also like to shoot some in my encore .223. now looking back at some comments on here they state that the 5.56 cases are thicker , so that being said i weighed a buch of the cases , and also some .223 cases and they all weighed pretty much the same, around 93.5 to 95.2 grs. now would'nt the 5.56 weigh more seeing that they are thicker? also would i have to go by nato loading data and then reduce that to shoot in a .223 barrel? any comments would be appriciated. ----thanks

[cwbys4evr]

Don't shoot 5.56 in your rifle unless it is chambered for 5.56. Second , I would be leery of giving anyone my loads to shoot, especially a loved one. Maybe that's just me, but if something by chance went wrong with something I loaded and hurt someone, I would feel horrible.