Quick question about C.O.A.L

T

Txbonecollector75

New member
I've read a lot on reloading but the biggest question I have is " case over all length ". I look at my Lyman reloading handbook and it says for a .223 Remington that OAL is 2.260", now I read my Lyman AR15 reloading handbook and it says OAL for a 55gr bullet is 2.260", but then I read Sierras AR15 reloading pages and it says for the same 55gr FMJBT bullet OAL is 2.250", and hornady 8th edition says for 55gr FMJBT OAL is 2.200", and looking at the hodgdon powders that I plan to use it says for a 55gr bullet OAL is 2.200".

I guess what I'm trying to ask is which one do I go by???
I know if you set your bullet to long it's not building up the right amount of pressure and if you set it to deep it builds up to much pressure, I'm needing help with this OAL please.
 
Go by the bullet manufacturers recommended length. Hornady's 55 FMJ and also their Spire Point with lead tip the recommended length is 2.200". The difference is mainly in the bullet point shape and ogive. Hornady's 55's have a blunt rounded tip while military and other 55 gr. bullets have a longer sharper pointed tip and overall lengths for them is usually 2.250". Also, 55 gr. bullets with plastic sharp pointed tips they usually recommend 2.250". And for AR 15's the maximum length that will feed from the magazines is 2.260". Lots of loaders say just to seat 55 gr. bullets with a cannelure to place the case mouth in the middle of the cannelure. Bolt action rifles have a shorter distance to the lands of the barrel than does the AR rifle. With 4 different bolt rifles in .223, 30-06, and 25-06 Hornady's oal recommendation puts the bullets about .050" from touching the rifling. In .223 Rem in AR's their is a much longer jump to the rifling. Start with recommended overall lengths from the bullet manufacturer.
 
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The Over All Length (COAL) in my opinion is important for many reasons. Some rifles have clips that will only handle so much case length before the bullet jams in to the front of the clip. So that is one example. In a 1911 the clip is so long and the feed ramp and barrel throat require certain length for the same purpose. Now if you have a Rem. or Win. ... bolt action rifle that you want to just feed one round at a time then the restriction of the COAL would be used to keep the bullet generally off the lands of the bore so the pressure doesn't spike causing a over pressure issue. In a Tomson contender a single shot pistol or a Ruger #1 rifle the same is the issue since you don't have a clip.

Then there is the COAL for tuning a round for accuracy. Some rifles like the bullet to be .020" off the lands some more some less some jammed in to the lands. That is another story story.

Maby some one can give you more.
 
First off, COAL is CARTRIDGE Over All Length. AKA "loaded length with bullet".

Second, the max COAL listed is a length that should work in all common firearms chambered for that cartridge. It is NOT a "rounds MUST = this number" It is a length that rounds will generally work through the action, and not jam into the rifling when chambered.

And, that's ALL it is.

Some guns will handle longer than "max COAL" length rounds. Some will not handle "max COAL" rounds reliably. Manufacturers generally load ammo a little shorter than listed max, to enhance its reliability over the wide range of possible firearms it will be used in.
 
I know if you set your bullet to long it's not building up the right amount of pressure and if you set it to deep it builds up to much pressure, I'm needing help with this OAL please.
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Txbonecollector75: Quite a few hand loaders make this assumption and it is incorrect. The most danger in seating a bullet is jamming it into the lands and not knowing.

There are quite a few articles written on the subject of bullet seating and pressures. Most have been written by reputable people and bullet manufacturers.

Do a little research on the subject so that you can learn these basics.
 
"Max COAL" is set by SAAMI. If a rifle doesn't work with 'em, something's wrong with the rifle.
SAAMI says 2.260" is max for .223. And that's measured from the pointy bit to the flat bit. No ogives involved. Click on Cartridge and Chamber Drawings.
http://www.saami.org/specifications_and_information/index.cfm
"...the bullet manufacturers recommended length..."Should also be the SAMMI length.
However, I've never had any issues whatsoever using the Max OAL(SAAMI) length given in my manual. If a MAGAZINE won't work properly with that length, it's a defective MAGAZINE.
 
I wish the manuals didn't even list OAL for rifle cartridges. It only serves to confuse people. Some manuals don't list it, in fact.

Load them so they fit and function in your firearm/magazine and try tweaking for accuracy, if desired. In this case, ignore the manual.
 
I guess I'll figure it out own my own! Since my original QUESTION was basically, why is it that some reloading manuals state that C.O.A.L. is 2.260" and another says its 2.250" and another says its 2.240" and another says its 2.200" and another says its 2.150". But thank you everyone for telling me to do more research or go look at SAAMI's website when I do know what SAAMI set standards are!
 
The coal listed in the manuals is nothing but a guide and indicates what the coal was when they tested the load.

Most guys figure what will fit the magazine since that determines the longest that you can have.

Figure what fits your mag, then make a couple of dummies at that length and chamber each one.

Remeasure to make sure that your starting coal is still there and examine the bullets to make sure that they did not contact the rifling in the barrel.

You may want to "paint" the bullets with a sharpie to enhance any markings that might show up on the bullets. If the bullets come out clean with no markings, then you have found the coal for that bullet.

I recommend starting out that you use the coal listed in the manual, then you can dinker with different seating depths if you need/want to.
 
Since my original QUESTION was basically, why is it that some reloading manuals state that C.O.A.L. is 2.260" and another says its 2.250" and another says its 2.240" and another says its 2.200" and another says its 2.150".
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OK, I'll try and hit this directly.

Take another look at those manual. Look carefully, and see if they identify the measurement as "max COAL" or not.

Max COAL is a SAAMI spec.

What you are seeing with different lengths listed is the actual loaded length of the round, with the bullet being used. NOT the listed SAAMI Max COAL.

Some loads ARE at the SAAMI listed max length. Some are shorter.

Let me give you another example. .30 Caliber 150gr bullets (both from Speer, in this case). One is a spitzer, the other a flat point. SAME WEIGHT.

Now lets seat them both so the base of the bullet is even with the base of the neck of a .308 Win case.

SAAMI MAX COAL for the .308 Win is 2.810"

My 150gr spritzer cartridge measures 2.800" (slightly less than SAAMI max)
My 150gr flat point (with the bullet seated to the same depth in the case as the spitzer bullet) measures 2.610".

SO my load manual with this bullet would list COAL as 2.610" Not the SAAMI max, but what the loaded round actually measured.

I think that is what you are seeing with the different listed lengths, NOT different MAX lengths, just the different lengths of the loaded rounds due to the different lengths of the bullets loaded.

Hope that explains you original question.
 
First, you got the pressure thing backwards. In a bottle necked rifle round , the longer the OAL the Higher the pressure and the shorter the OAL the less the pressure.

To make life easier for yourself, just ignore the OAL listed in the manuals, it means nothing to you and your firearm.

When loading for an AR the longest OAL that will fit in the mag is 2.260 That is basically all you need to know, except....

The only other thing you need to be concerned with is neck tension. The rule of thump is to seat the bullet at least one bullet diameter into the case. In the 223 AR that would be .224 inches of bullet seared into the neck.

Ingnore the OAL in your manals
 
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"I guess I'll figure it out own my own! Since my original QUESTION was basically, why is it that some reloading manuals state that C.O.A.L. is 2.260" and another says its 2.250" and another says its 2.240" and another says its 2.200" and another says its 2.150". But thank you everyone for telling me to do more research or go look at SAAMI's website when I do know what SAAMI set standards are!"

Those numbers are what the ballisticians used to get the data they printed.
 
I guess I'll figure it out own my own! Since my original QUESTION was basically, why is it that some reloading manuals state that C.O.A.L. is 2.260" and another says its 2.250" and another says its 2.240" and another says its 2.200"
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All good info so far to help you out including the correct wording for the acronym . COAL stands for cartridge over all length . Case length is the distance from the head to case mouth of an unloaded case .

I'll add that not all 55gr 223 projectiles are the same length . Really most projectiles of different manufacturers regardless of caliber or weight are not the same length ( the bullet it self ) . Even with in the same brand the same weight and caliber can differ in length quite a bit

Some bullets have short stubby noses while others have long thin pointy ones . So "if" you seat the bullet .224 deep in the case some bullets will stick out farther then others changing the COAL from manufacture to manufacture . Your manual/s will explain all this in the beginning in the bullet seating section .
 
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Yes, that's what I was wondering guys. Thank you, I was needing a plain and simple answer not a real technical one. I want to say thank you again because now I understand what all the different lengths for the different bullet types mean.
 
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