Difference between 5.56 & .223 when reloading

Skitty112

Private
Minuteman
Feb 17, 2021
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0
Paris, Tennessee
Hello all! I’m a little new to reloading and have a question. I’m sure you’ve been asked a billion times, but this time I would like multiple people to chime in. I’m getting conflicting answered by most people on fb and would like to hear your thoughts. Please also describe in detail what makes the difference between reloading .223 vs 5.56. And what should I watch out for when doing so? Do I have to separate my cases? Do I have to add more of a charge for 5.56 or is it the same charge as .223? These are all questions I have. Please let me know. Thanks!
 
I understand there is some minor difference in the shoulder between 5.56 and .223.

5.56 tends to be a hotter military load.

Before the internet people never knew there was a difference.

I dont think unless special ordered you will find dies marked 5.56.

There are already multiple threads on this with multuple people chiming in.

Start low, work up.
 
I understand there is some minor difference in the shoulder between 5.56 and .223.

5.56 tends to be a hotter military load.

Before the internet people never knew there was a difference.

I dont think unless special ordered you will find dies marked 5.56.

There are already multiple threads on this with multuple people chiming in.

Start low, work up.
Yes, I have searched most other threads but never found the direct answer to my question. I guess my question is this...... when you full length size a 5.56 case, does it then become a .223 case? Also, if you only size the neck rather than full length size will the case remain a 5.56 case? Or, is the difference between .223 and 5.56 only in the barrel chamber and NOT anything to do with the case itself?
 
Yes, I have searched most other threads but never found the direct answer to my question. I guess my question is this...... when you full length size a 5.56 case, does it then become a .223 case? Also, if you only size the neck rather than full length size will the case remain a 5.56 case? Or, is the difference between .223 and 5.56 only in the barrel chamber and NOT anything to do with the case itself?


Who cares.

5.56 is a higher pressure round with a shitty mass produced ball round typically.

.223 is loaded with some bullet designed to do terminal damage to some sort of animal.

Most of us shoot to make small groups on paper or splat steel.

If shooting AR separate your cases if you want (certailnly for developement), squeeze them up in a quality die, put in some non existent primer, powder and bullet of your choice, shoot the amount of powder at a length that works best in your rifle.

If you are shooting bolt and want to blast a ground hog at 600 yards buy Lapua brass, the finest ELR bullets, match primers and do extensive load developement.

If the 5.56/.223 stuff bothers you get a Wylde Chamber.....understand it cares little what you shoot.......

Ill save you time......Dillon .223 dies, 23.2 +/- of 8208XBR, 77 SMK, whatever SRP you can find, 2.25 OAL, just call it your gun that shoots little bullets with no recoil and forget about the metric/english caliber designation.
 
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There are no dimensional differences between a 5.56X45 and a 223 Remington cartridge. A quick look at the cartridge dimension diagrams in both SAAMI and CIP specifications will show you that.

There are differences in max allowed chamber pressure depending on whether the cartridges were loaded to SAAMI or CIP specs.

The chamber dimensions are different depending on whether the person doing the chambering followed SAAMI specs, CIP specs, or something else entirely

I'm not going to dig up those specs for you OP. Go find them and read them if you want to understand how this works.
 
Do you have a reloading manual?

Look at the SAAMI specs.

Then look at the load data.

Usually, a manual will list loads for heavier bullets for the 5.56 whereas the loads for 223 are typically for lighter bullets.
 
This is simple , if you have a .223, load using .223 recipes, if you have a 5.56 you can use .223 and 5.56 load recipes. Case external dimensions are the same for both, the difference will be the internal case volume . Lots of myths and downright BS about internal volume , only way to know is to measure .
 
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Get off of FB.
Buy an actual reloading manual like the Hornady.
Pour yourself a coffee and read it.
Look up actual reloading data in the manual and make comparisons.

Your answer is within.

If you take the time to actually read real data and a real manual, you won't get all twisted up with nonsensical opinions from the internet warriors.
 
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Get off of FB.
Buy an actual reloading manual like the Hornady.
Pour yourself a coffee and read it.
Look up actual reloading data in the manual and make comparisons.

Your answer is within.

If you take the time to actually read real data and a real manual, you won't get all twisted up with nonsensical opinions from the internet warriors.
Funny you say that on a internet forum, and plainly express your opinion just like the so called warriors .
 
Funny you say that on a internet forum, and plainly express your opinion just like the so called warriors .

Oh first fuck's sake.
Grow some thicker skin or
go back to FB and stay confused.

I offered you a lightly tongue in cheek solution to your question. You got your panties all twisted up over it.

Lighten up Francis.

I know how to reload.
I know how to research information for correct answers.
I know how to separate the wheat from the chaff.
I don't ask for answers to questions that can be answered by attaining a little knowledge rather than hearsay on the web.


BTW, my opinion is based on facts.
 
Oh first fuck's sake.
Grow some thicker skin or
go back to FB and stay confused.

I offered you a lightly tongue in cheek solution to your question. You got your panties all twisted up over it.

Lighten up Francis.

I know how to reload.
I know how to research information for correct answers.
I know how to separate the wheat from the chaff.
I don't ask for answers to questions that can be answered by attaining a little knowledge rather than hearsay on the web.


BTW, my opinion is based on facts.
You seem pretty stupid., and think your pretty tough . Troll much ?
 
Oh first fuck's sake.
Grow some thicker skin or
go back to FB and stay confused.

I offered you a lightly tongue in cheek solution to your question. You got your panties all twisted up over it.

Lighten up Francis.

I know how to reload.
I know how to research information for correct answers.
I know how to separate the wheat from the chaff.
I don't ask for answers to questions that can be answered by attaining a little knowledge rather than hearsay on the web.


BTW, my opinion is based on facts.
What's a trunk monkey ? Sounds like a girl's club .
 
Cool, but thought I would ask the guy spouting off . I'm sure you are an ok guy in real life , some folks just like to hide behind a computer and act tough . You can be anyone you want on the internet , even a good person if you choose .
 
Cool, but thought I would ask the guy spouting off . I'm sure you are an ok guy in real life , some folks just like to hide behind a computer and act tough . You can be anyone you want on the internet , even a good person if you choose .

I don't hide. My location is clearly listed in my profile.

With that said,
I didn't notice until just now you aren't even the OP.

Nice troll job.
9/10 for your work.👏👏
 
I don't hide. My location is clearly listed in my profile.

With that said,
I didn't notice until just now you aren't even the OP.

Nice troll job.
9/10 for your work.👏👏
This shit is the exact reason to say fuck it and not help people. Social media and the web will be our downfall, if it is not already. Carry on, your posts are always solid.
 
This is simple , if you have a .223, load using .223 recipes, if you have a 5.56 you can use .223 and 5.56 load recipes. Case external dimensions are the same for both, the difference will be the internal case volume . Lots of myths and downright BS about internal volume , only way to know is to measure .
That depends only on the brand of brass used.

As a general rule, military brass tends to run thicker walls than civilian brass giving a smaller internal volume. But that is not a hard fact, and in any case one can load to 5.56 CIP pressure with civilian brass.

The bottom line is that the differences are ALL external to the cartridge itself. The differences are all in the maximum average pressure and in the chamber dimensions.
 
case capacities resized.jpg



...
 
Yes, I have searched most other threads but never found the direct answer to my question. I guess my question is this...... when you full length size a 5.56 case, does it then become a .223 case? Also, if you only size the neck rather than full length size will the case remain a 5.56 case? Or, is the difference between .223 and 5.56 only in the barrel chamber and NOT anything to do with the case itself?

Dimensional specs for 5.56mm and .223 cases are identical.
Both tend to have similar capacities with variations being due to manufacturer rather than 5.56 or .223 designations.
There is no such thing as 5.56 brass or .223 brass, the differences are due to loaded cartridge pressure ratings and chamber leade length, (a 5.56 nato chamber has a .125" longer leade than a SAAMI 223 chamber) rather than the shape or thickness of the case.
C.I.P. sets max service and proof pressures for the .223 equal to that of the 5.56 nato at 62,366 p.s.i.
SAAMI sets max pressure specs for the .223 at 55,114 p.s.i. due to C.I.P. test protocol measuring using a drilled case rather that an intact case with a conformal piston.
NATO uses NATO EPVAT pressure protocols for it's small arms ammunition and set pressure limits at 62,366 p.s.i.
The early military version of what became the 5.56 NATO was little more than the commercial 223 Remington cartridge adopted in 1963 for use in the M16 rifle and renamed Cartridge, 5.56mm Ball, M193 with specs calling for a Remington designed 55gr FMJBT bullet loaded with IMR 4475 powder with a MV of 3250 fps and a max working pressure of 52,000 psi.
Cartridge, 5.56mm Ball, M193 was never a NATO round, and it is fully interchangeable with commercial 223.
 
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Cool, but thought I would ask the guy spouting off . I'm sure you are an ok guy in real life , some folks just like to hide behind a computer and act tough . You can be anyone you want on the internet , even a good person if you choose .
Easy there Karen... Sure there's a bit of irony there but the guy knows what he's talking about and just gave you really good advice.

Just say "Thank You".
 
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223 and 556 chambers are different. 556 chambers are larger. This allows the 556 round to be hotter. 223 chambers are tighter and the max pressure ceiling is lower. You can shoot 223 in a 556. The velocity will be lower because the larger 556 chamber will cause the 223 round to develop less pressure. But you should not fire 556 in a 223 chamber because the tighter 223 chamber will cause the 556 round to exceed the max pressure and you might have pierced primers stuck cases etc.
 
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223 and 556 chambers are different. 556 chambers are larger. This allows the 556 round to be hotter. 223 chambers are tighter and the max pressure ceiling is lower. You can shoot 223 in a 556. The velocity will be lower because the larger 556 chamber will cause the 223 round to develop less pressure. But you should not fire 556 in a 223 chamber because the tighter 223 chamber will cause the 556 round to exceed the max pressure and you might have pierced primers stuck cases etc.
That all depends....
20210219_185659.jpg
 
I agree that in general the 5.56 will have an extra thou or two of space for fouling etc to ensure reliability and of extra freebore for the same reasons and used to be generally heavier and thus longer bullets.

These days with people tinkering and optimizing reamers and Wyldes etc and brass sorts there isn’t a whole lot of beans worth in difference. Keep your brass sorted to like lots and start low and work up.