.308, 30-06, 7.62 mix up! Please help!


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dscottw88
October 8, 2007, 11:19 PM
According to Wikipedia... "The .30-06 Springfield cartridge (pronounced “thirty ought six”) is a .308 inch (7.82 mm) (.300 inch is 7.62 mm) caliber rifle round, also known as the 7.62 x 63 mm, introduced to the United States Army in 1906 (hence “-06”) and standardized, with use continuing into the 1960s, tapering off in the 1960s and early 1970s."

So which is it? .300, or .308?

I thought that .308 is equivelant to 7.62 but in the article it says its 7.82.

Maybe i'm a complete idiot but I thought that the 7.62 NATO had the same dimensions as the .308 Winchester. Guntech, please help. lol.

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R.W.Dale
October 8, 2007, 11:25 PM
7.62 or .300 refers to the BORE diameter

whereas .308 denotes the bullet and or the groove diameter.


Kinda like 38 special which DOESN'T shoot .38" diameter bullets but shoots .357 slugs



basically the numbers in a cartridges name mean obsoletely NOTHING 307 win is a prime example. Or better yet 7.62x51R = 30-30 and 7.62x51nato = .308 win. Confused yet?

Kimber1911_06238
October 8, 2007, 11:29 PM
.30-06, .308, .300 wm, etc. all use .308 diameter bullets NATO calls them 7.62 for reasons that krochus has already explained

Not sure where the 7.82 came from, most likely a misprint

Acheron
October 8, 2007, 11:56 PM
7.82 is not a misprint. It's the actual diameter of a .308 bullet. The math proves this: 0.308 x 25.4 = 7.8232.

anymanusa
October 8, 2007, 11:57 PM
fix it then! wiki is editable by the user.

ArchAngelCD
October 9, 2007, 03:44 AM
Take what you read on Wikipedia with a grain of salt. Many things are correct but just as many entries have errors. As you know everything is posted by users and not checked by anyone who really knows.

As for a 7.82mm round having anything to do with a 30-06 Springfield or .308 Winchester, well, it just doesn't. I have never heard of a 7.82mm round even though I guess it does exist somewhere.

The 30-06 = the 7.62X63mm NATO
The .308 = the 7.62X51 NATO
The 7.62 is a 30 Caliber bullet but really measured .308" in the 30-06 Spring., 30-30 Win. and the .308 Win.

Acheron,
Even though your Math is correct the numbers are wrong. The bullet is a 30 Caliber bullet, not a 308 Caliber bullet. That would make the correct formula .30" X 25.4 = 7.62 Exactly!

yesit'sloaded
October 9, 2007, 03:58 AM
Lets make it even more confusing:evil: 7.62x39 is 7.62 soviet and 7.62x54r is 7.62 russian. they have bore of .311

ArchAngelCD
October 9, 2007, 04:01 AM
yesit'sloaded,
Actually the R in 7.62X54R doesn't mean 7.62 Russian, it means 7.62 RIMMED.

Jim Watson
October 9, 2007, 08:39 AM
.300" = 7.62mm is the bore diameter of most nominal .30 caliber rifles. They drill and ream a hole of that diameter through the barrel blank. Then they cut (button, broach, or hammer forge) the rifling grooves. Cut an even number of grooves .004" deep, measure from the bottom of one to the bottom of the opposite, and you get .308". Which equals 7.82mm and is where you get the 7.82 Lazzeroni Warbird if you like fancy advertising.

It is usual in the USA to make bullets equal to the groove diameter of the barrel.

So there are caliber designations by the bore diameter or by groove diameter for the same thing. 7.62 NATO based on bore diameter is the military version of the .308 Winchester based on groove diameter.

Cut five .005" grooves in a .300" bore and you get a US 1917 Enfield, with a nominal .310" groove diameter, although it is hard to measure in a five groove barrel. It shoots .308" bullets quite well.

Cut .0055" - .006" grooves in a .300" bore and you are making a 7.62 Russian, either 7.62x54R MN or 7.62x39 AK, which take .311" bullets.

jerkface11
October 9, 2007, 08:51 AM
So what about 7.5x54 and 7.5x55 they both use .308 bullets.

TexasRifleman
October 9, 2007, 08:58 AM
Maybe i'm a complete idiot but I thought that the 7.62 NATO had the same dimensions as the .308 Winchester.

Yes and no :)

The chamber dimensions are different, but no one makes brass that is to the 7.62 dimension, only the .308 except for some odd machinegun ammo you don't see for sale any more.

It only matters if you are shooting commercial .308 in a rifle with headspace outside the SAAMI limit but still within the NATO limit. If you have one of those rifles you should only shoot NATO marked brass.

Jim Watson
October 9, 2007, 09:07 AM
So what about 7.5x54 and 7.5x55 they both use .308 bullets.

I believe the early 7.5x55 Swiss had about a .304" bullet in a corresponding barrel and they just did not change the designation when they changed bullets.

As to 7.5x54, who knows why the French do anything?

jerkface11
October 9, 2007, 10:15 AM
Ok then what about 7.65 argentine mauser?

yesit'sloaded
October 9, 2007, 10:46 AM
Make it stop! Mommy make it stop! My head hurts now. I knew the r stood for rimmed, I just thought the cartridge was referred to as 7.62 russian to differentiate it from 7.62 soviet. Kinda like everybody knows 7.62 NATO is talking about 7.62x51 instead of 7.62x63. Except there is a 7.62x63 NATO so it can be even more confusing. I'm just gonna keep putting bullets in my gun that fit right and go bang.

USSR
October 9, 2007, 10:57 AM
...there is a 7.62x63 NATO...

Please show me a cartridge headstamp for a .30-06 round with a NATO symbol on it. The .30-06 was NEVER officially adopted by NATO.

Don

TexasRifleman
October 9, 2007, 11:10 AM
Well NATO may not have adopted it but the term is used a lot.

Here is an example from the entry rules on a 3-gun match I saw a while back....

4.3 Rifle ammunition shall be .223 Remington (5.56 NATO) or larger. (HM Class: .308 Winchester/7.62x51 NATO or 30-06/7.62x63 NATO only.)

I've never seen one with the NATO headstamp either but the name is sure used.

ArchAngelCD
October 9, 2007, 11:56 AM
You guys are right, the 30-06 was never adopted by NATO, I shouldn't have added the NATO at the end of the 7.62X63mm.
Ok then what about 7.65 argentine mauser?
jerkface11,
The 7.65 Argentine Mauser is a 32 Caliber round. For some reason the 7.65mm bullet is considered a .32 caliber even though the Math doesn't add up. I'm guessing it's something like the .38 Special. That bullet is really .358" but still called a .38. Just look at the .32 Auto, it's original designation is 7.65mm Browning.

USSR
October 9, 2007, 12:33 PM
I've never seen one with the NATO headstamp either but the name is sure used.

Only by those who don't know better. As previously stated, Wikipedia is not a good source of information. IMHO, the biggest problem with the internet is, someone posts something that is patently false, and then people quote it as a source and don't ask themselves if it is true or even logical.

Don

TexasRifleman
October 9, 2007, 12:42 PM
As previously stated, Wikipedia is not a good source of information.

I was seeing that term used WAY before there was a Wikipedia, and as the example I posted shows, used by people that surely should know better; in this case the organizers of a 3 gun match here in Texas.

That term has been used for a very long time so I'm wondering what the origin is. It ain't Wiki :)

Maybe Europeans use the term? Interesting if not useless trivia anyway :)

jerkface11
October 9, 2007, 12:44 PM
Ok how about the lazzeroni .30 cals they're marked as 7.82mm.

Gewehr98
October 9, 2007, 12:52 PM
Their whole lineup's that way.

See Jim Watson's explanation above.

Drilled bore/bore at lands = .300", or 7.62mm
Bore diameter measured at two opposing .004" rifling grooves = .308", or 7.82mm

There's 25.4mm/inch.

Not so difficult once you wrap your head around the concept. ;)

Bwana John
October 9, 2007, 01:02 PM
:evil:and then there is the pistol and SMG 30's:

7.62mm x 17mm Browning (32 ACP)
7.62mm X 25mm Tokarev
7.62mm x 38R Nagant
7.63mm Mauser
7.65mm Parabellum (.30 Luger)

Jim Watson
October 9, 2007, 01:04 PM
7.65 Argentine (Wonder why the Belgians don't get the credit?) shoots a .311" or .312" bullet. 7.65 mm converts to .301" and is probably the bore diameter or close to it, with rather deep grooves to hold up with hot 1889 powders.

7.65, 7.7 Jap, and .303 British barrel dimensions are so close as to overlap within tolerance limits. Chambers are completely different.

ArchAngelCD
October 9, 2007, 06:14 PM
Bwana John,
Even though this is getting very old very fast I have to correct something you posted. You said the 7.62X17mm Browning = .32 Auto but that's incorrect. The correct designation is 7.65mm Browning for the .32 Auto.

I have a box of Fiocchi 7.65mm Browning ammo in my hand right now.

alsaqr
October 9, 2007, 06:22 PM
"I have never heard of a 7.82mm round even though I guess it does exist somewhere."

Yep, it does, the 7.82 Lazzeroni Warbird.

http://www.lazzeroni.com/ct_lacart.htm

Sunray
October 9, 2007, 08:43 PM
"...My head hurts now..." That'd be the brain damaged caused by trying to figure out why cartridges are named what they are. Goes away when you stop thinking about it.
Most commercial cartridges are named for marketing reasons. Modern military cartridges are, usually, named to avoid confusion with another country's or previously issued, military cartridges.
As mentioned, mathematically, 7.62mm converts to .30 inches, but .308" doesn't convert to 7.62mm. .308" converts to 7.82mm. 7.62 is the bore diameter across the lands. .308" is the nominal diameter across the grooves.
Since NATO came along, military cartridge designations have been metric.

Hypnogator
October 9, 2007, 10:36 PM
Since NATO came along, military cartridge designations have been metric.

Errr..... Actually, not. European cartridges have been designated by bullet diameter and case length for over a century, now. :uhoh: (e.g., the 7x57mm Mauser used in the Spanish-American War.)

Jim Watson
October 9, 2007, 11:14 PM
Yes, but they had not been able to cram it down Americans' throats before.

jpwilly
October 10, 2007, 01:11 AM
...good thing I don't have any NATO reloading manuals!

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