What do you actually size your 223 cases to?

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Unique Username

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What do you actually size your 223 cases to?



OK… I’m kind of out in the weeds here. I mostly load 45 ACP and I haven’t loaded for the AR in about 7 months.



I measured my fired cases and they were coming out pretty consistently at 1.461, so with a .004 shoulder bump they come out to be approximately 1.457. But that number seems low. Like, less than SAAMI minimum cartridge low. Which is 1.459.

So I got to thinking… there are literally endless discussions about cartridge headspace online, but no real list or collection of what people are actually sizing their cases to. I mean, there’s really small margins from biggest to smallest so it should be pretty easy to see an average. But I’m just wondering. SAAMI vs. The World I guess. Just informational and maybe a reason for someone to re-examine how their resizing die is set up if they find themselves way outside the average.





My resize: 1.457

Saami chamber: 1.463 min / 1.473 max

Saami cartridge: 1.459 min / 1.466 max
 
How are you measuring to SAAMI specs?

I can measure my actual headspace gauges using my comparators, and not get the actual SAAMI specs.

My comparators are just that, they compare, but don't measure against specs, and honestly it wouldn't matter if they did because my chamber "is what it is" so I size to fit that.

For my bolt .223s (all bolt guns for that matter) I size for a .002" "Bump" after the brass is fully formed, sometime 3-4 firings. Semi's with precision ammo get .003-.004". General purpose .223 fired in multiple rifles gets FL sized.
 
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I’m use the Hornaday comparator. The real reason I’m asking this question is because I was resizing 200 cases to my usual 1.457. During the process I stuck a case in the resizing die. While taking it out I must have messed with the setting a little bit and never re-checked it before I continued on resizing. ( my bad, yes )So in the end, I ended up with 63 cases that were 1.46 and over. Some of them as much as 1.4635. So then I started wondering if I needed to resize them all down or just go with them and see what happens with cases that are .006 over what I usually size to. That’s why I looked at the SAAMI specs again and that’s how I came to the conclusion that my original resizing was under their minimum cartridge length number. So what are other people actually sizing to? Maybe my numbers were off too small because my cases were never fully fire formed when I measured them initially and got my numbers.
 
Unique Username said:
What do you actually size your 223 cases to?
Click to expand...

Either the rifle they are to be used in or a case gauge.

Looks something like this, either way but don't need the rifle if using a case gauge.

www.youtube.com

Setting size die for bolt action rifle.

www.youtube.com www.youtube.com

I've done it like this on semiautos too.

www.youtube.com

Setting size die for AR type rifle.

www.youtube.com www.youtube.com

Once they are right for the chamber they are pretty close on the case gauges and once they drop into the gauges they would certainly fit the rifle, both methods will make ammunition that will run, without excessive case growth/trimming required upon sizing, etc.
 
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I size the brass to fit the chamber, and don't worry about SAAMI spec as chances are the rifle isn't exactly to spec.

I have two (rookie numbers I know) ARs chambered in 223. One is 223 Wylde, one is 5.56 chambered. Obviously the chambers are different but I want all my blaster ammo to fit in any gun. The Wylde chamber is tighter than the 5.56, so it grows less with every firing, verified with a comparator.

At this point I measure the brass shot from the Wylde chambered gun, and then full length size, bumping the shoulder back 5 thou. This ensures every round I load, fits in any gun, including my friends rifles. How that compares to SAAMI, I don't know and don't care. I just want function that works everywhere. Am I allowing the brass shot in the 5.56 gun to grow more because if memory serves, it does grow about 8 thou more than the brass from the Wylde gun, so the 5.56 guns brass does get worked a little more because I am moving the shoulder about 13 thou to bring it to my spec.
 
Charlie98 said:
That's my method. I feed 4 different AR's, albeit all with 5.56mm chambers, but I just mash them all. FWIW, even though I FL size, there are differences in shoulder location... some brass is harder than others, and doesn't size as readily.
Click to expand...
This is exactly what I see as well. Im less concerned about the perfect sizing with my 223, I just want everything to run anywhere in that platform.
Rifles that have specific brass just for that rifle? Im far more picky.
 
The only ammo I size in my AR is what I use for hunting, otherwise I am not that critical as long as it fits in the magazine and chambers.
 
Over the years I adjusted my RCBS .223 (not small base) sizing die to deliver resized cases that would reliably chamber in each of the two Mini-14s and two AR-15s that I load for. That setting has not been changed since 1982.
 
Unique Username said:
I measured my fired cases and they were coming out pretty consistently at 1.461, so with a .004 shoulder bump they come out to be approximately 1.457.
Click to expand...
Are you sizing the case, or just bumping the shoulder? And shouldn't they grow if you're sizing?

I'm getting a bit confused here, but that's not always hard to do.

chris
 
Charlie98 said:
That's my method. I feed 4 different AR's, albeit all with 5.56mm chambers, but I just mash them all. FWIW, even though I FL size, there are differences in shoulder location... some brass is harder than others, and doesn't size as readily.
Click to expand...

Even then they're probably quite a bit undersized as the majority of ARs I've checked headspace on will close on a no-go gauge, but not a field gauge.

But since it's .223 and fired in an AR, most likely to get lost well before case head separation.. no big deal.
 
ballman6711 said:
Are you sizing the case, or just bumping the shoulder? And shouldn't they grow if you're sizing?
Click to expand...

A FL die not cranked all the way to the shell holder, because of case body taper, can just resize the neck, up to the point the die contacts the body and shoulder. Not sure how many 223 dies I have but don't own any neck only dies, all are full length.

If you are moving the shoulder with a bump or a shove, you are resizing the case, changing its dimensions from what it was.

How much the case length grows depends on how much "under" the case was and blown out upon firing. If your die is set like that first video in #5 you won't have to trim as much as you would if it were set for that wilson case gauge (and allowed to expand in the clearance created by the additional sizing) but the likely hood it functions in the largest number of firearms goes up with brass that's smaller than needed vs larger than what will fit.
 
irishlad said:
I FL size em to pass my Wilson gauge.
Click to expand...

I can put a piece of fired .308 brass, from my M1a no less, in my Wilson case gauge and it will pass. As I understand it, the Wilson gauges, at least the rifle ones, are to simply measure base to shoulder length, and then shoulder to case mouth length. I mention this because when I first got my Wilson, I mistook what it's function was.
 
Charlie98 said:
I can put a piece of fired .308 brass, from my M1a no less, in my Wilson case gauge and it will pass. As I understand it, the Wilson gauges, at least the rifle ones, are to simply measure base to shoulder length, and then shoulder to case mouth length. I mention this because when I first got my Wilson, I mistook what it's function was.
Click to expand...
I have one Wilson gauge, 7.62x39, and it's a minimum chamber gauge. I did quite a bit of looking at their site before I bought it, and found they make a few different types of gauges. I have three 7.62 rifles and wanted the ammo to fit all three.

chris
 
Horses for courses.

I have multiple 223's, and make multiple "classes" of ammo for them. One of my 223's is a heavy barreled bolt gun, it doesn't get blasting ammo, so I make ammo for it which is suited ONLY for its chamber, same deal for my hunting ammo for one of my AR's in 223/5.56 - both of these rifles get ammo made just for their chambers, with no regard to any other barrel in the house, and I don't worry whether other ammo would fit, feed, or function in them (although I know that most of my ammo WILL Triple F in all of my rifles). A couple of my 223's are blast-o-matics, so they get ammo which is made with a small base (equivalent) die turned all the way down to touch a Redding shellholder (slightly shorter than most other brands) - so that ammo will fit and go bang in any chamber I've ever used.
 
Thanks for all the replies. I do have the LE Wilson gauge. The 1.4635 cases are juuuust a little above the top step, but I tried a few in the rifle and the bolt closed fine and extraction seemed normal…. but so does the 1.457 cases lol

What all comes down to is this, and why I posted in the first place … If you read enough reloading forums you will hear so many dire warnings about sizing cases. Too short and you’ll get head separation… and you will blow your face off, or if you size the case too long you’ll get an out of battery detonation which will also blow your face off… So if the cases I have are 1.457, ( too short = blow my face off), or 1.463, ( too long = blow my face off ) the difference in that is merely 6/1000 of an inch.

So with all the warnings about too much or too little headspace, no one really ever mentions what their cases are sized to, in numbers, using a comparator. But lots of people will readily tell you what SAAMI minimum and maximum chamber and cartridge is.

I’m interested in extending brass life. Oh, and also not blowing my face off.
 
Unique Username said:
I’m interested in extending brass life. Oh, and also not blowing my face off.
Click to expand...

I would like to think those are mutually exclusive. I've mashed all my rifle brass to minimums for years... and I still have my face attached, for whatever that's worth. I'm more concerned with weak brass... which actually did try to blow my face off, but that is a whole other story.

Probably the biggest thing you can do to extend the useful life of a case is to anneal the neck.
 
Get a case gage.

Get a box of M-193 ammo.

Push the shoulder of your re-sized brass so that it matches the measurement of M-193 in the case gage.

If you are a benchrest shooter (or similar) do whatever you want.

But if you're shooting the ammo in a semi-auto, IT MAKES NO SENSE to size brass to any other shoulder dimension than the dimension that exactly matches M-193.
 
Charlie98 said:
I would like to think those are mutually exclusive. I've mashed all my rifle brass to minimums for years... and I still have my face attached, for whatever that's worth. I'm more concerned with weak brass... which actually did try to blow my face off, but that is a whole other story.

Probably the biggest thing you can do to extend the useful life of a case is to anneal the neck.
Click to expand...
I never realized how prone to splitting 223 was. Might have to look into a machine....
 
I don't have many neck splits with .223 cases. I can get 8 to 12 firings on them before the primer pockets get loose enough to toss, without annealing.

Maybe my chambers are simply not sloppy, dunno.

Then again, I have seen a fellow shooters batch of .223 cases split 50% of their necks the second firing.
 
223 bolt rifle used in modified type bench shooting. With the Hornady comparator I size my brass to 1.461" - 1.462".. I also trim back cases to 1.755" and run them out to the max of 1.760".. Before sizing they are coming out of this rifle at 1.463"
 
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