5.56/223 cases

[Gullwing]

Have acquired a couple of thousand x military 5.56 once fired cases,I have been told that there are some minor differences between them & .223 cases.Can the 5.56 cases be reloaded using the powder & jacketed bullet specs for a 223 rifle I have; a New England Handi Rifle SC2 break open single shot.?? that I would like to reload for. Thanks for any safe info.

 

[Gadawg88]

Short answer is yes. You will need to remove the primer crimp after you deprime.

 

[Frankl03]

Its my understanding that 223 will fit a rifle chambered for 556 but not the other way around.

I'm sure there will be someone along soon that is more knowledgable on this.

 

[cfullgraf]

The differences between 223 Remington and 5.56 NATO is in the chamber. The cases are made to basically the same dimensional specs.

Unlike 308 Winchester/7.62 NATO, 5.56 NATO cases do not necessarily have less internal volume than the commercial counterpart so, except for normal load work up processes, military and commercial 223/5.56 cases can be interchanged without issue. Military cases do not necessarily generate higher pressures as with 308 Winchester.

Note that most military 5.56 NATO cases have crimped in primers. The crimp needs to be removed before they can be easily re=primed.

Hope this helps.

 

[steve4102]

Long answer, "Yes". They are the same and will remain the same after removing the primer crimp and running them through your 223 die.

Next question, "Is it true that the 5.56 cases have less case capacity then 223 cases". Answer, NO, in fact, most 5.56 cases have more case capacity than 223 cases.

 

[Gullwing]

5.56 //223

Thanks eveyone for all your help its much appreciated. I can set to now & enjoy myself, ( & save some cash )

 

[z7]

most of my brass is 5.56 brass, either WCC or LC headstamp. it works well after you remove the primer crimp. i have gotten my best group with a nosler 55g varmageddon and WCC brass of .6" for five shots out of my AR15, i tried to repeat and got .7"

remove the primer crimp, resize trim and load.

 

[spitballer]

Good question and it's hard to get a simple, authoritive answer to it. Aside from the obvious difference of the longer leade, I suspect that the 5.56 chamber might be just a tad looser also, which would mean that fire-formed cases would have a similar capacity to the .223. This is only speculation.

 

[Panfisher]

Deprime, remove primer crimp, clean, resize, trim. Then they are exactly like every other .223 Rem stamped case. The vast majority of my cases are range pickup 5.56 mil stamped cases. Removing the primer crimp is the biggest PITA but only has to be done once. Trim them back to min length and load away. I fully resize my cases by making sure the shell holder touches the bottom of the die at the full stroke, and they have worked perfectly.

 

[steve4102]

I suspect that the 5.56 chamber might be just a tad looser also, which would mean that fire-formed cases would have a similar capacity to the .223. This is only speculation.

Maybe, but, no.

Case capacity is checked in grains of H20 of fired cases from the same firearm. Different firearms may produces difference capacity from the same case, never compare case capacity from range pick-ups or from different firearms.

 

[homatok]

With respect to projectiles for the military chambered 5.56x45/223, Speer says military rifles likely have a twist rate of 1 in 7 inches and are intended for 62 grain military ammunition. Several bullet makers compared notes and all had the same observation: muzzle velocities over 2800fps in a 7" twist will tear apart conventional 22 caliber bullets. For a rifles with a 1 in 7 inch twist, try 62 grain FMJ or 70 grain semi-spitzer to keep bullets together. Handloaders must be aware of twist rate when shopping for a 223 rifle. The standard 12" twist is best for varmint-class bullets. While the 5.56x45mm NATO will fit in a .223 Remington chamber, the 5.56 is a military round that runs at higher pressures than its .223 counterpart and is not recommended to be fired in a .223 Remington chamber.

 

[bancroft]

primer crimp

Hi folks just how do you remove a primer crimp .
thanks

 

[vongh]

I use a chamfer tool chucked in a drill to remove the crimp. Others use a primer pocket swaging tool or a primer pocket reamer.

 

[wanderinwalker]

Take the 5.56 cases with the arsenal head stamps, run them through your .223 sizing die and you're good to go. Well, OK, after you remove the primer pocket crimp and trim the cases back to length.

5.56 cases may in fact have the same or greater case capacity than a commercial .223 case. Federal comes to mind right off the bat with having soft, heavy, low volume cases compared to certain lots and years of LC brass. Nine to 10 years ago at least I preferred Lake City cases to commercial brass when loading my Highpower match ammo because the LC cases held a bit more powder and held up to more loadings than any others. With the recent improvement in the supply of .223/5.56 ammo, a large number of crimped LC, WCC and FC stamped brass has ended up in my buckets. Once sized, swaged and trimmed, I treat it all the same. I also keep my reloads well under max so I can just grab whatever cases are ready and go to work.

My only gripe with any of the NATO-stamped brass is that it tends to be LOOOOOONNNGGGG after resizing and requires quite a bit of material be removed.

Several bullet makers compared notes and all had the same observation: muzzle velocities over 2800fps in a 7" twist will tear apart conventional 22 caliber bullets. For a rifles with a 1 in 7 inch twist, try 62 grain FMJ or 70 grain semi-spitzer to keep bullets together.

I've read this online a couple of times but never experienced it in real life. I have seen bullets come apart when fired in fast-twist match bullets, but they weren't the type of bullets this wisdom says should have. (In fact they were heavy 75-77 grain match HPs.) My suspicion is it has more to do with the smoothness of the rifling and the thickness of the bullet jackets. We don't experience rashes of complaints about standard 55gr .223 bullets coming apart when fired in a typical 1-7" twist M-4gery or A2-type AR. And I'd be surprised if M193-type ammo does much less than 2900 in a 16" carbine; my chronograph says my "mild" reloads of 55gr FMJ over 24.5gr of H335 run around 2850-fps.

In fact one of my favorite 100-yard loads for use in a 20" Service Rifle with a 1-7" twist barrel is a 52 grain match HPBT over a max charge of W748. Never had any accuracy issues or bullet disintegration. Any "accuracy" issues with 5.56 ball ammo is more likely tied to the bullet quality than the rate of rifling twist it's pushed through.

 

[Walkalong]

The bullets one needs to worry about twist rate and velocity with are the very thinly jacketed varmint bullets. Speer puts out a warning about the .22 Cal TNT bullet. Perhaps others.