223 vs 5.56 cases

hounddawg : keep in mind one of the reasons it's recommended to measure/weigh case "volume" rather then weight is because "WHERE" that weight is in the case matters . Maybe you have a slightly thinner extractor groove and thicker rim the extractor grabs . That case may weigh .5 to 1.0gr more then another that has a thinner rim and larger extractor groove but they both could have the same internal case volume and vise versa .

Weighing cases is not the best way to check the consistency of a given lot of cases .

If you look at the 223 case weight to case volume chart in this link about 1/4 to 1/3 of the way down the page you will see what I mean . There are cases that weigh as much as 7gr more but only .1gr difference in case volume . That extra case weight must be somewhere in the case that does not effect case volume . Assuming it's an accurate chart . It's a perfect example why only weighing cases is a waist of time .
http://www.6mmbr.com/223Rem.html
 
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Thanks for the tip metalgod, I will go by volume when I start sorting. On my bolt rifles I have been using commercial brass. I have around 550 of these guys to trim before sorting. I am currently waiting on a die for the Lee Quick trim to make it's way down to me on the UPS truck before tackling that job.

What I can do though is later today I will trim 25 to length using my Wilson trimmer, then record the case weight and the volume then later on acquire some Lapua and do the same.

This is just another of my little experiments to see if I can turn range pickup into match ammo. Lapua .223 is not that expensive and before all is said and done I will have a lot of time invested in these. By the hour these cases will be the most expensive I have ever obtained
 
Exactly. Weight is a poor predictor of capacity both because the several alloys used by different brass makers have different densities, but mainly because differences in the diameters of heads and angle of the extractor groove's tapered leading edge allow for weight differences that have no effect on capacity because they are below the part of the case that holds the powder. An example:

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extractor groove's tapered leading edge allow for weight differences that have no effect on capacity because they are below the part of the case that holds the powder
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I have said a case head thickness of less than .200" is a dangerous case. I have said I have 30/06 cases heads that are .260" thick, I have also said I have thousands of cases with a case head thickness of .200". Of the two case head thicknesses the .260" is my favorite.

And then there is the discussion about heavier and or lighter. My thin case headed cases are the heaviest. After that deductive reasoning has to be applied: problem, I am the only reloader that measures the thickness of a case head.

And then there have been some wild guestimates of case head protrusion and unsupported case heads, again, when given a choice I prefer the thick case headed case.

F. Guffey
 
Interesting that the NATO STANAG drawings for M80 7.62 NATO brass cases specify a thickness of 0.175". Of course, they also specify hardness of the head that is expected to be met and that is greater than in commercial brass, so the tensile strength is higher.
 
And then there have been some wild guestimates of case head protrusion and unsupported case heads, again, when given a choice I prefer the thick case headed case.
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MY thoughts as well. Glad you brought that point out Mr. Guffey.

Also, from my experiences, my milsurp brass has less case volume than all others. It is mostly LC from the late 50s & 60s. I have to adjust powders charges down by 2-3 grains to keep the load performance the same as WW brass. This is in 30-06 (7.62x63)
 
I stick to mid range loads and sleep well at night. If I would have to sort every case, fill them with water, weigh the water, write in a notebook etc.... I would just buy my ammo.
 
All the 60's and 70's vintage LC .30-06 I've measured has weighed approximately 194 to 196 grains. Remington has run around 190-194 over the last 25 years. Winchester used to be about 180 grains, like an LC 7.62×51 case. More recently, though, it has been more like 185 grains. In the old NRA book, Handloading, Wm. C. Davis had .30-06 cases as heavy as 214 grains, IIRC (old Peters, I think; I'd have to check). So, last long enough and you see all kinds of unexpected things.
 
I wanted to get a full lot of 50 that were plus or minus a grain and it took measuring 76 cases. I think this is a good representative sample. Once I determined the year manufactured and dry weight were not a factor I stopped noting them. Only had 2 really wild readings on which I blew the cases out with compressed air and remeasured each one. One was over 36 grains and the other 34.8 grains. The rest were 35.5 plus or minus .2 grains. I think we can safely say LC is some pretty darned consistent brass.

Once I get my barrel in I will give them another anneal, neck size and a quick bath before loading and shooting. Then do a baseline chrono to note the velocity SD. Afterwards they will be annealed and neck sized after each firing with a full length sizing every
5th firing. I want to see how many times I can reload before primer pocket issues or neck splits.

Just the nerd in me but I find these little experiments fascinating
 
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Remington has run around 190-194 over the last 25 years.
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My Rem. & RP brass, well, damn near all my brass is at least 40 yrs old. I still have some NIB brass that I haven't placed into service yet from the late 60s & early 70s.

Back then, my RP & Rem. brass had less case volume than any of my other brass. Most times I shied away from loading it due to the fact, and loaded WW almost exclusively.

BUT, when powder charge was adjusted properly, some amazingly accurate ammo came from those cases.
 
Interesting that the NATO STANAG drawings for M80 7.62 NATO brass cases specify a thickness of 0.175".
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I am not going to tell anyone it does not matter. I measure case head protrusion, for example I have at least 40 Mauser barrels. It is almost like I know the case head protrusion is going to be .110" before I measure it. The .110 does not include clearance, the clearance could be .005". That moves the bolt face back to .115". And then there is the case friendly radius; point, I want all the case head support I can get because I have no guarantees something is not going to seriously go wrong when I pull the trigger.

I have shot a few very heavy loads, a few have been so heavy the case head was crushed, the primer pocket opened up and the flash hole was as large in diameter the primer pocket; did the case head thickness natter? It did and does to me, the case head thickness was .260", I could have used a case head with a thickness of .200" but if the case head thickness was .175" all of the fun would have disappeared in one big bang.

F. Guffey
 
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The ranges in my area are maximum 200 yards. I zero & load for that distance . The listed starting load for a 308 cal. 168gr. Sierra HPBT MatchKing bullet using IMR 4064 is 41.0 gr. Im shooting accurate 1/2" groups with no issues 40.8gr. What is the need for speed , hard on the rifle & brass .If it can get the job done with less , what is the need . Am I missing something.
 
What is the need for speed , hard on the rifle & brass .If it can get the job done with less , what is the need . Am I missing something.
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Yes you are missing something....but not with your application.

1: Speed helps reduce wind drift at long range. Studies were conducted at 1000 yards, finding increased velocity helped increase the likelihood of hitting the xring a significant percentage of the time. (You can Google to find the study).

2: speed increases your maximum point blank range for hunting.

3. Speed increases the energy imparted on the critter you are trying to kill and many bullets will not achieve the best terminal ballistics at low velocity. Plus, you get the "shock" effect with velocity.

4: a full rifle case, which usually comes with velocity unless using a really slow powder, ensures the case powder "packing" will not change regardless of how you tip the case or shake it.... basically the bullet locks it in place giving more consistent results .

5 : increased velocity helps reduce how much your scope has to travel at long range to zero.

6: velocity helps move the transonic zone out further thereby ensuring the bullet is stable at longer ranges.

But if all you shoot is 200 yards, wind isn't much of a factor, the transonic zone is more like 700 yards so no issue there, at 200 yards, inconsistent velocity will not affect poi that much, and terminal perfomance is irrelevant when punching paper. So in your case, velocity doesn't do much to hurt/help you.
 
1. 223 and 556 brass are identical dimensions. Variances are low between brands and milspec.
2. What IS DIFFERENT is the chambers of each and every gun. 556 have a longer leade/throat to accept longer bullets. Thus Accurate/Ramshot/Wester powders list 556 loads in a separate block. These are for use in 556 chambers and can handle longer bullets and COAL. What brass you use does not matter much, the chambers are different.
3. Some 223 chambers like a Savage Axis I have will chamber the longer bullets. A better Savage I have is tight on COAL Spec and wont chamber anything longer.
So, more than being a brass question, this is a chamber question, snd the reloader needs to understand the chamber of each of their rifles.
I agree on the need for speed, if you shoot long you are going to load hot.
 
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I agree on the need for speed, if you shoot long you are going to load hot.
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Need for speed: I had no need for speed, one more time, I purchased 4 rifles that were sold to me as 'SUSPECT'. Change the subject: I purchased a barrel from a custom shop got $5.00. I asked them what was wrong with it. They said they did not know, they said all they knew about the barrel was 'it just did not shoot'. Back to the rifles I purchased; they did not know why the rifles were suspect. All I knew about the rifles? They had been shot enough to ware out two barrels.

I had no need for speed, I needed to know what 'SUSPECT' meant, so I basically did the same thing Col Jackson and his soldiers did, They melted the cannons barrels down and then grabbed an alligator and loaded him up then powdered his behind. They claim when they set the powder off the gator lost his mind.

Again, I used one barrel and one bolt on all 4 receivers. One smith in Arizona went to a lot of trouble identifying the chamber based on my measurements. He is the one that thought I was involved in some risky stuff. I called Hodgdon, they said my fire forming loads could be at or above maximum after the cases was formed, I backed off on the weight of the bullet by 50 grains and reduced the amount of powder I was using by 6 grains after the cases were formed.

F. Guffey
 
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They melted the cannons barrels down and then grabbed an alligator and loaded him up then powdered his behind. They claim when they set the powder off the gator lost his mind.
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Well then, I guess that explains everything.
But what chambering of gator was it?
 
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