Might have bumped the shoulder too far?

[cw308]

Getting back to the subject, The Outlaw is not using the best brass 5.56 in a 223 chamber, yes you can size it to work, good practice, brass is probably thicker. Poor choice of brass, reloading for the first new setup. Outlaw don't beat yourself up. Remove your primers before measuring your cases, F/L size your brass, don't oversize, start with your die backed out , size , look at the sized neck, screw the die down alittle at a time until it sizes to the bottom of the neck without bumping the shoulder. See how it works from there

[The Outlaw]

Originally Posted by The Outlaw

Sized brass in question
1.461
1.459
1.460
1.459
1.459
1.458
1.458
1.459
1.458
1.460


M855
1.451
1.450
1.450
1.451
1.449
1.450
1.449
1.449
1.450
1.449


Fired from this rifle
1.454
1.454
1.455
1.455
1.455
1.454
1.455
1.454
1.455
1.454

Fired same 10 855 rounds measured above and 7 of them measured 1.456 while 3 measured 1.455little5.
That would mean I should never size longer than 1.453?

[cw308]

The Outlaw, l feel you could keep your reloads at 1.455 not less and you will be fine. try 20 rounds see if to your brass gets longer. Just remember when measureing brass remove the primer . a bumped out primer can screw up your numbers. Think of why people neck size, when the case gets to long they bump the shoulder back. I never liked the idea of neck sizing for accuracy due to case bodies are different lengths. Keeping your F/L sizing to 1.455 let's see where your brass winds up. What powder , load in grains & bullet and weight are you using with AOL for magazine.

[F. Guffey]

It would appear your sized cases are on the minimum side and your fired cases are below minimum length; meaning your fired cases are shortern than your sized cases if we are talking about the length of the case from the shoulder of the case to the case head.

F. Guffey

[cw308]

F.G, l feel that's what his problem is, that's whats stumping him.

[PA-Joe]

How did you screw the die down too far? It has to stop on the shell plate doesn't it?

[mehavey]

OUTLAW,

- Your fired cases are expanding to the sides of the chamber (good).
- As a result, they are getting "fatter" (normal).
- Because chamber headspace is good and the case doesn't stretch out lengthwise,
..it actually gets slightly shorter as the sides bulge out to the chamber (solid geometry)

Don't sweat it.

As you then resize, the sides are squeezed in, the case gets longer again, and the
die re-sets the shoulder to the baseline (you established earlier from feeling for bolt closure).

Yer doin' fine.

[The Outlaw]

I'm just getting more confused.

I took surplus m855 that averaged 1.450 head to datum. And shot it in this rifle and it stretched to a 1.456 average meaning they grew about 0.006. These were not reloads

The LC brass I sized were 1.459 on average which is 0.009 longer than the unfired surplus so if your saying I sized to the minimum then that m855 would hame been way shorter than minimum specs. If what i just read elsewhere is true 1.463 - 1.473 is the min/ max either the hornady guage is WAY off or the m855 ammo was also way under minimum

[The Outlaw]

One place says 1.463 - 1.473 another says
1.4666" with a tolerance of minus .007"

That's a pretty big difference
.I don't know if it's an information overload or lack of sleep but the more I try to wrap my head around it the more retarded I start to feel lol.

[mehavey]

SAMMI spec on the case (see drawing) is 1.4666-0.0070"
http://labscdn2.luckygunner.com/labs...r-791x1024.jpg

That's (effectively) 1.460" to1.467" (a 7 thousandths band) for the case.


NOTE the civilian GO Gauge for the chamber is 1.464" (i.e., 4 thou bigger than the shortest case);
and the chamber NO-GO is 1.467" (right at max SAAMI case length)
http://www.ar15barrels.com/data/headspace.pdf

......BREAK, BREAK.....

Remember that you are running a Hornady comparator --not an exact Headspace gauge.
All you care about is that the sized case comparator dimension for loading is just ever-so-slightly smaller than the just-barely-fits case.

[The Outlaw]

With the m855 I had reading shorter than that would you attribute that to the m855 actually being shorter than that or the hornady gage being off that far

Edit. You posted before me that answered the question.

[mehavey]

My Hornady 'A' gauge measure of my unfired brass at

Lapua 223            1.454
PMC 223              1.456
Win 5.56             1.454
REM 223              1.456
FED M193/5.56        1.454
BlkHills(Remanf) 223 1.452

So it varies a bit, and "measures" (comparatively) smaller that SAMMI Min.
But I don't care. All I care about is that I know what it should read when resizing to fit my Krieger chamber: 1.460"

[Metal god]

Do your 1.459 cases chamber easily in your rifle ?

Remember all factory ammo is likely going to be closer to the minimum then the maximum . When reloading we generally want are cases closer to the maximum length . When I say maximum length I mean maximum in comparison to your chamber . This helps extend the life of your brass .

The XM855 should have plenty of pressure to blow your cases out . I'm starting to come around to the thinking as others have said . That is that your chamber may be a little on the fatter side .

I believe others have touched on this but I'll mention it again . If your 1.459 cases chamber when lightly clambering them with the FA . They should be fine and would also say the XM855 rounds are sized much closer to minimum spec . Why there not being blown out to your chamber size is the new question . At least for me it is . There are a few reasons why that could be happening but not sure if it really matters for you though . It's just one of those , hmm things that I like to understand .

[The Outlaw]

Could it have anything to do with being a .223 wylde chamber?

The .223 Wylde is a proprietary rifle cartridge chamber with the external dimensions and lead angle as found in the military 5.56×45mm NATO cartridge and the 0.2240 inch freebore diameter as found in the civilian SAAMI .223 Remington cartridge.

Yea they all easily chamber.

[The Outlaw]

Mehavey I think that may be the answer. Doing it that way is going to give me the same result I would get with any other tool even if they all call that same end result by a different number.

I still want to get both the wilson gage, and the rcbs mic. I figure they will give me peace of mind at least. If I use all 3 and note the measurements, anytime I worry something is off with one of them I can verify with the others. Yes I have adhd real bad lol

[F. Guffey]

Then there is the chamber, measuring the chamber; a chamber cast is one of those topics that can not be discussed in a reloading forum. Reloaders do not know how and they do not want anyone to know. A chamber can be measured for length from the shoulder to the bolt face at least three different ways. Reloaders with an infatuation with head space gages us the go, no and beyond gage and that is it. I want to know the length of the chamber from the shoulder to the bolt face when it is measured in thousandths.

One more time, I have an Eddystone M1917, the chamber is .002” longer than a field reject gage, or..016” longer than a minimum length/full length sized case, or .011” longer than a go-gage length chamber. None of this drives me to the curb or locks me up. When sizing/forming cases for that chamber I adjust the sizing die off the shell holder .014” with a feeler gage then size/neck-up 280 Remington cases to 30/06.

Bump the shoulder? The shoulder on the 280 Remington case does not move.

F. Guffey

[cw308]

The Outlaw, leave your die set to the longest case setting, all your measurements I'm sure are correct, the brass just isn't stretching, l shoot benchrest only, I size my brass to .001 headspace. 308 cal. Bolt action 1.629 if some case reading are 1.627 or below I don't use for target shooting. Doesn't mean they wouldn't fire, may only get 6 reloads instead of 25