223 reloading

[Nasty Ned]

Am not new to reloading but am to the 223 loading. My question is; when loading GI brass do we need to cut back the powder charge from what is shown in our reloading charts, or use the same charge for both GI and commercial cases?????

NN


Thanks in advance for your answering this.

 

[rcmodel]

No.

In my experience, military 5.56 brass is no thicker then commercial brass.

This is not true on GI .308 and 30-06, as it is thicker.

But I have a bunch of Remington .223 brass that weighs more then any GI brass I have.

What you need to do though, is weigh some trimmed .223 brass and some 5.56 brass you are using and compare the weights.

If it weighs more, it has less capacity.

Scroll down in this link to the part about brass weight and see the results.
http://www.6mmbr.com/223rem.HTML

Rc

 

[JimKirk]

My finding are just like RC's .... also the LC brass are some of the lightest ...

 

[Potatohead]

Anybody wanna bet that RC is right?

 

[Bull Nutria]

Not betting against RC not me. I learned so much about this stuff from him i read everything he posts!!! Keep your money don't bet against RC!!!

Bull

 

[345 DeSoto]

^^^^
What HE said...

 

[W.E.G.]

Lapua is the known offender of diminished .223 case capacity.

I can't tell any difference in case capacity between LC and commercial.

Be careful judging case capacity on weight of the case.
When comparing by weight you must be cognizant of wide vs narrow extractor groove and neck length.

 

[Bexar]

I ditto RCM's findings which I found several years ago weighing new RP brass against some cleaned and processed LC brass from Jeff Bartlett. I'm glad this question was posted as I was wondering the same thing. The question has to be asked...since the outside dimensions have to be the same...where is the difference made up in the case? Web...wall thickness...heavier brass...etc.

Thanks

 

[243winxb]

If it weighs more, it has less capacity.

What you need to do though, is weigh some trimmed .223 brass and some 5.56 brass you are using and compare the weights.
< This.

 

[cosh]

+1. And check case capacities. The brass density varies too. Had some (didn't write it down) that weighed more but capacity was within 0.2 grains of the regular LC brass.

 

[Bexar]

Question...how important is the difference between LC and RP brass? It would seem that unless you're on the hot side of the firewall with your loads a discrepancy so small wouldn't have that much of a difference.

 

[rcmodel]

That's the way I always treated it.

Same load, any cases.

I don't load near close to max, and shoot the same loads in three different rifles.
I have used the same load of W-748 since the early 1970's.

The only thing I do, is sort by headstamp on my CZ-527 varmint rifle, and use the same brass in it so it is always zeroed exactly at long range.

The AR & Mini-14 are minute of clay pigeon accurate at 100 yards with any headstamp so I don't worry about it.

If I was loading on the bleeding edge pressure wise, I'd be much more particular about head-stamp.

rc

 

[Walkalong]

Same here, my plinking ammo is safe in the heaviest of .223 cases I am likely to be using. Occasionally I will have a case come around to have a bullet seated where the powder is much higher (Well into the neck), and I pull those out. They either have some trash in them taking up space or simply have a lot less capacity than the average case. Scrap them and move on.

 

[oldreloader]

RC is right on once again!

 

[steve4102]

What you need to do though, is weigh some trimmed .223 brass and some 5.56 brass you are using and compare the weights.

If it weighs more, it has less capacity.

Not entirely accurate.

From the link you provided.

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



Note that in several instances the heavier case had more capacity than a lighter case.

For example the Federal case weighed 96.3gr @ 30.2gr H20.

Hornady, IMG, Lapua(new lot) and Radway all weighed less than the Federal and also had Less capacity.

Another example from your link,

WCC99 weighed 95.5gr @ 30.5gr H20. S&B brass weighed less by 3,2gr @92.3. yet it had identical capacity @ 30.5gr H20.

So, by the chart linked there really is no direct correlation to case weight and case capacity. Just because a case weighs more does bot automatically indicate less internal capacity.

 

[fallout mike]

Steve, everything you mentioned is so close it makes no difference.

 

[steve4102]

It still indicates that there is no direct correlation between case weight and case capacity.

Weighing a case will tell you one thing, How much it weighs. Weighing it will tell you nothing about internal capacity.

everything you mentioned is so close it makes no difference.

Take a look at the Lapua (old lot) and the PMP.

Both have almost identical weights 104 and 104.5gr. One could assume that they are so close it makes no difference, yet the Lapua (old lot) has almost 2 gr less case capacity. In my book a case as small as a 223/5.56 with 2 less grains in capacity is a Big Deal.

 

[X-Rap]

If I was weighing all my 223 brass and checking its water capacity I'd never get to shoot. If I had a specific rifle and was a high end bench rest competitor I'd probably have a couple hundred rounds at a time that I might check in this way but even then I'd probably shoot them all first to judge if it was really necessary. Since I process all of my 223 brass by the bucketful I just try to keep threads like this out of my head bad enough worrying about having enough powder.

 

[Walkalong]

While steve 4102 is right about case capacity and weight, almost no one does it that way vs weighing cases for the simple reason that weighing is such a great deal easier.

We all weighed heavily prepped 6PPC cases to group into small batches, but they were all from the same maker/lot and that is much more reliable than weighing range brass from multiple makers/lots.

For .223 plinker loads that are, as rcmodel puts it, not on the bleeding edge of max, weighing cases will work just fine. And as I posted, if a case comes along on the LNL that has the powder much higher up in the case than usual, I pull it from the press and scrap it.

And to answer the OP's question again, in the case of GI 5.56/.223 cases, some are heavier, and some are lighter, than commercial brass, which of course also varies between makers.

GI .223 tends to be about the same, while GI .308 tends to be heavier, which is where the thought comes from when folks ask about..223 being heavier.

 

[cdself]

I'm not sure what you're loading for, Ned, but you may want to consider OAL and bullet weight as you assess whether you will use max published loads with your brass in the cartridges you're loading based on capacity. Example: If you are loading light bullets so they touch your lands in a long throated rifle (assuming you can do it), you will have a very different capacity than loading heavy 77 grain projectiles mag length for an AR.

 

[fallout mike]

Steve, both are right at the bottom of the chart on case capacity. Like RC said, if it weighs more it has less capacity.

 

[gamestalker]

RC is definitely among the top, of the top 10, when it concerns this hobby, trust his advice like that of any professional.

But to further address the question, anytime I'm loading a bottle neck cartridge with brass that I haven't previously developed with in that firearm, I follow safe recommended protocol, that being, working up from a reasonable starting charge. Not necessarily the bottom of the table, but reasonable, maybe at 50% table or so. If pressures don't appear out of the ordinary, I'll move up in larger increments until I'm at the point of fine tuning.

What I don't do, is I don't just jump into full pressure loads without first observing pressure signs at a slightly lower table charge.

GS

 

[steve4102]

Steve, both are right at the bottom of the chart on case capacity. Like RC said, if it weighs more it has less capacity.

The chart lists case weight and case capacity.

Please explain in detail how the WCC99 weighing 95. 5gr with 30.5gr of H20, has less capacity then the S & B case weighing 92.3gr with 30.5gr of H20.

My math must not be none to goodly. The S&B is 3.2gr lighter so it should have more capacity,but it does not, what am I missing?

I'm all eyes, show me the error in my thinking.

 

[fallout mike]

It's like a 3% difference. As stated by several, if you aren't near max you're good to go.