.223 / 5.56 Cases

[Good Cheer]

Just to satisfy my curiosity about "military" brass...
Wanted to compare case volume on various head stamps of brass.
So, took ten pieces of brass from each stamp, full length sized, trimmed and primed.
Filled ten cases level from a bowl of BLC2, doing my best to be consistent, then weighed the powder from the ten cases.

Here's the results I got with this brass:
Winchester = 303.0 grains
RP = 303.8 grains
Hornady = 298.6 grains
PSP = 302.5 grains
LC = 303.3 grains
WCC = 302.2 grains

Couldn't resist breaking out the calculator and running percentages averages, extreme spread, deviation from average. For that small a case volume it's certainly enough to make a difference in what load you build on which case.

[rhbrink]

Thats why it pays to start low and work your way up anytime you change anything. Especially brass and powder even if the powder is from the same manufacturer. Some powders seem to vary quite a bit from lot to lot in my experience anyway.

[Three44s]

+1 on powder lots having a BIG influence sometimes!

Three 44s

[Good Cheer]

I ran that survey of cases due to being told that military cases were of smaller capacity. Those results do not appear to indicate such.
Is there a suitable ball powder that is less sensitive to loading density?

[GabbyM]

Alliant has a new ball powder out for the 223.
Power Pro Varmint.
I've not heard any reports yet.

[spqrzilla]

The advice that military cases are of smaller capacity mainly applies to .30-06 arsenal brass. To a lesser extent it applies to .308Win/7.62NATO brass.

But I've never seen any indication that .223Rem/5.56mm cases differ much between commercial and military. There is more variation between them by manufacturer rather than by intended use.

[BruceB]

"But I've never seen any indication that .223Rem/5.56mm cases differ much between commercial and military. There is more variation between them by manufacturer rather than by intended use."

I agree 100%.

I once weighed samples from at least a dozen different groups of .223/5.56mm cases, that is, both military cases of various dates and factories, and commercial cases from a variety of manufacturers.

There was NO MEANINGFUL DIFFERENCE in the average weights of all the various groups. After that exercise, I stopped concerning myself with the subject. Occasionally I will check the average weight of a new batch of cases, but I don't lose sleep over it.

As mentioned, there definitely IS a weight difference between military and commercial brass in7.62 NATO/.308, and in the .30-06 brass as well.

[Gunnut 45/454]

Good Cheer
Ah sorry but .223 Rem/5.56mm case only wt 94 grains plus or minus! So I don't know what you used to weight them but it wasn't grains and it wasn't grams then they only come out 6.17g plus or minus! I do agree there is not much difference between them but 5.56mm has a thicker case head and are .010" longer at the neck . This why I trim 5.56mm to 1.760" and Rem .223 at 1.750".:mrgreen:

[303Guy]

Gunnut 45/454, that was for powder charges. Still 303gr powder in a 223 case and the anomality went right past me![smilie=1: Decimal point in the wrong place maybe?

[missionary5155]

Good morning
The text says " He weighed the powder from 10 cases" Not one case.
Mike in Peru

[JeffinNZ]

I have a large quantity of FNB 5.56 brass I picked up at the range over a number of months. The headstamps are 04 and 06 and there is a 5gr variation between year of manufacture.

[pilot]

I have a large quantity of FNB 5.56 brass I picked up at the range over a number of months. The headstamps are 04 and 06 and there is a 5gr variation between year of manufacture.

Thanks, that reminds me, I have to take a sack to the range tomorrow. You can pick through the barrels there.

[JeffinNZ]

Thanks, that reminds me, I have to take a sack to the range tomorrow. You can pick through the barrels there.

Amazing isn't it? I made some nice "primer/powder" money picking up 5.56 brass, cleaning and sizing then on selling.

[pilot]

Amazing isn't it? I made some nice "primer/powder" money picking up 5.56 brass, cleaning and sizing then on selling.

I'm not planning on selling any yet. I got 55 rounds of 7.62x39 and a couple hundred 223 while waiting for the range to clear. I just want brass to load.

[JIMinPHX]

In my experience with .223 cases, PMP & RORG headstamp cases have much smaller capacity than the rest. LC, WCC, RP, FED & Winchester headstamp cases were all about the same. I have been told that older LC cases ran small, but I never saw that myself. I've tested most years of LC after 95 & a few as far back as the '70's.

Please be aware that some of the WCC stuff is made here by Winchester & some of it comes from IMI. I think that the Israeli stuff has a Q in the part number on the box or something like that. The two may not be quite the same.

[donald duck]

For my 7 MM TCU I check length to be 1.749. Run the .223 brass through a .25 die and then the .284. Only lost a few brass sizing a bunch last week. My case lube is Shaler Rislone drippings from adding to my Honda Pilot. I think it makes a good bullet lube. Loading 5.0 to 5.3 grains of Unique behind a 120 grain cast GC bullet. I did use 6.5 grains of Tite Group
behind 90 grain cast GC Bullet in my Rem. 700 .243. These loads are for paper punching and inexpensive to shoot.

[madsenshooter]

The volume of the .223 case used can make a difference in your results. I'd followed some other advice I'd found on here. The consensus was, there wasn't a substantial difference between military and commercial brass. So after getting a good accurate load for 6x45 in FC 06 cases, I made up the same in PRVI cases in preparation for a match. The accuracy was not nearly as good, and I could tell that pressure in the PRVI cases was lower. Though I didn't do too bad in the match, I think it would have been better if I had used the same lot of cases. When dealing with things smaller, seemingly minute differences can mean a lot! Here's how the test load on FC 06 cases shot a few days before the match. Though conditions were about the same, I imagine the groups increased to about 1.8".

http://castboolits.gunloads.com/imagehosting/thum_12364e5f028b65d83.jpg (http://castboolits.gunloads.com/vbimghost.php?do=displayimg&imgid=1993)

[tomme boy]

Both have a trim length of 1.75" in every manual i have seen.

[GabbyM]

You can find deviation in web thickness from brand to brand. The 5.56mm Mil Surplus brass falls in within the range of variation between commercial brands. Even if brands weigh out the same they won't shoot together. Same with mixed head stamp Mil brass. Even mixed lot numbers on commercial brass is pretty iffy. The ten ring on a 200 yard I.B.S. Hunter Rifle target is about 7/8".

If you buy a bag of 100 new cases it’s best to get a 100 round box and keep them in that for life. Write the lot number off the bag onto the box. Half the time after you cull them you’ll only have around seventy five cases in the box. I’ve got around 500 243 Win cases with Win head stamps from three lots. Let them get mixed up after a prairie dog shoot years ago. They are sub par now. If they are just loaded with soft nose hunting bullets you can’t see the difference to much. You’ll get those flyers from a ten shot group. Shot about forty last week with 87gr V-Max and they made two vertically spread groups on the targets with a few hits in between at 200 yards. That’s after weight sorting. Was still shooting one hole groups. Just that all the groups weren’t in the same place. Then there were those in between. Shot five over the Chrony and one was over 100 fps out. Scratched that one then had an 8fps E.S. on the other four. Oh well.

[nicholst55]

In my experience with .223 cases, PMP & RORG headstamp cases have much smaller capacity than the rest. LC, WCC, RP, FED & Winchester headstamp cases were all about the same. I have been told that older LC cases ran small, but I never saw that myself. I've tested most years of LC after 95 & a few as far back as the '70's.

Please be aware that some of the WCC stuff is made here by Winchester & some of it comes from IMI. I think that the Israeli stuff has a Q in the part number on the box or something like that. The two may not be quite the same.

My experiences are the same as yours, Jim. I've reached the point where I won't hardly mess with foreign .223 brass, unless somebody donates a boatload of it to me!


Both have a trim length of 1.75" in every manual i have seen.

FWIW, all the once-fired USGI 5,56mm brass that I've ever worked with mikes some .010-.015" over that nominal measurement. Take a look at the dimensions on the link below, and you'll see why.

http://www.ar15barrels.com/data/223vs556.pdf

[tomme boy]

Fired brass is not the same as TRIM LENGTH. The only differance between the 223 an 5.56 chamber is the throat. 5.56 has a long throat to lesson the psi. 5.56 runs at a higher psi than 223, that is why the long throat. Consider the 5.56 like a Weatherby chambering.

[303Guy]

In my experience with .223 cases, PMP & RORG headstamp cases have much smaller capacity than the rest. PMP 303 Brit brass also has less capacity than other brands. A lot less!

[nicholst55]

Fired brass is not the same as TRIM LENGTH. The only differance between the 223 an 5.56 chamber is the throat. 5.56 has a long throat to lesson the psi. 5.56 runs at a higher psi than 223, that is why the long throat. Consider the 5.56 like a Weatherby chambering.

You're absolutely right - my point is merely that once-fired 5.56mm brass tends to be significantly longer than once-fired commercial .223 brass.

[tomme boy]

Because of the higher psi. That would be why it would be longer.

[Gunnut 45/454]

tomme boy
I suggest you take a .223 Rem and a 5.56mm load and look at them side by side -the 5.56mm is a longer case! It comes out to about .010" and this is why when I load 5.56mm I trim to 1.760" not the .233 Rem trim length of 1.750" this allows the extra 1-1.5gr powder charge above the manuals with out compression!
IE true 5.56mm loads!

[tomme boy]

Gun, the length of the neck has nothing to do with internal capacity of either case. If you think it does you should not be reloading.

Also every manual made shows the trim length at 1.75" So if you are trimming to 1.76, you are wasting your time. Trim them to 1.75 and you will be able to fire them 2x's before you have to trim them again.

Myself, I don't trim anymore. I have so many extra cases, I load them once and fire them. I just take them to the scrap yard.

[badbob454]

tommie boy maybe you should re think this, a longer caseneck allows the bullet to be seated further from the base, allowing more powder area .. me thinks

[tomme boy]

Not if the OAL is the same between the two. If the OAL gained the .01" along with the neck length then I could see the added space. But just the neck being longer will not add space. The Mil brass is not ment to be reloaded and no thought is given for it. If the added length is real, I don't believe it. It does not really matter anyway as each gun is going to have a little differant chamber length. Make a cast of your chamber an see what it really is. 1.76 is the suggested max.

I lined up 20 differant 5.56 cases and it looked like waves on the ocean for the neck length. 55an 62 grain was looked at. Then I lined up some factory and they did vary but not as bad as the Mil. Remember, the ammo was made by the lowest bidder. As long as it goes bang and does not blow up the gun it is good enough for the Military. They would have to really try to mess things up to not meet the I think 4 MOA standard.

[Gunnut 45/454]

tomme boy
Ah been reloading for 30 plus years! Are you dening the facts as I posted? The 5.56mm case is longer-period! This is why you don't shoot 5.56mm in a .223 Rem chamber! Cause you'll be shoving that case into the throat area and this is why it can blow the gun-causes extreme pressure spike! Ever look at the ORIGINAL spec sheet on the 5.56mm? It was a 60,000psi cartridge! They have revised it down to a 55,000 psi round thats still 5,000 psi over the SAMMI spec for .233 Rem.
SAMMI still warns against firing 5.56mm in a .223Rem chamber do they not!

OK here are two more pics two different makes of 5.56mm I also have IMI if you need that for comparision!!! Are you still going to deny that 5.56mm is longer then .223Rem? And before anyone flaps there gums -NO I didn't cherry pick these rounds all were just pulled out of BRAND new box or off a stripper clip.

[tomme boy]

I'm not dening anything. Like I said, I lined up a bunch of 193 and 855 and the neck was all over the place for length. You just happen to have a consistant lot. Oh, and show me 1 instance of a 223 firearm that has blow up. And it is not the length of the neck that is differant. The throat is longer on 5.56. And it runs at a higher PSI.

I have heard the same thing from other reloaders. "I have been doing this for 30 years!!!!" That does not mean you know what you are doing. I have seen more people blow stuff up with 30 years reloading than some one that has been doing it for 6 months. The new reloader is very cautious about everything he does. Us older reloaders get very complacent about what we do. We know everything. Myself included.

[Gunnut 45/454]

tomme boy
Well you get yourself a nice tight chambered .223 Rem an shoot 5.56mm through and when it lets go don't come crying to me! I'll not do the search but I've seen the pics, read the stories behind not only bolt guns but AR's chambered in .223 Rem letting go. SAMMI says not to shoot 5.56mm in .223 Rem chambered gun- I think they know what they are talking about. Read an article on it and someone actually pressure tested it and on average a 5.56mm ran into 87,000 psi in a .223Rem chamber- do you feel lucky!

[tomme boy]

Like I said, Show me one gun that was blown up by shooting a 556 in a 223 gun. When a AR lets go, it was from having the wrong powder, or metal fatiuge of the bolt or extension, or a blockage.

And I had a Savage FP10 that I had Fred at Sharp Shooters Suppy do a complete build for me about 3 years ago. It was in 223 Rem with a Rock Creek 5R Stainless barrel with a 1 in 9 twist. It was throated to run Sierra 69gr MK. Head space was set at Very min. I ran 50 rounds of LC 01 M193 threw it just becuse that was all I had that day. Shot right at 1" No hard bolt lift. No ejector mark or any kind of marks on the case head.

[badbob454]

tomme boy , i agree the oal will give you the same capacity , . period i too shoot 556 in my .223 handi rifle and have never had to push the round into chamber no problems maybe the chamber is made longer to accept the .223 and 556 as many think the 2 are identical , this would be smart on the gunmakers part ... ..
here is a must read for us that have a .223 cal. only rifle
http://www.ar15armory.com/forums/556-223-Ammunition-Ch-t22582.html

[Idaho Sharpshooter]

Am I the only one here that missed the charge weight being for all ten? I don't think my 22-378Wby AI cases will hold THAT much powder...

Rich

Nice Hi-jack by the way