calibers?

[RLsnow]

well being pretty less than educated about guns and such

im confused about caliber stuff like

.223 is the same as 5.56mm
7.62 is the same as .308
there is 7.62x54 and 7.62x32(i think)

could anyone clarify to me what all this stuff means and the many names for the same ammo?

 

[General Geoff]

It's not the same; there are subtle differences. As an example, read this description about the differences between 7.62x51mm NATO and .308 Winchester.

 

[Regolith]

.223 is the caliber designation, which uses standard measurements, and means that the bullet is .223 inches in diameter.

5.56 is the metric designation, and means that the bullet is 5.56mm in diameter.

These rounds are more correctly labeled 5.56x45mm NATO and 7.62x51mm NATO.The second number in the 5.56x45mm sequence, 45, designates the length of the cartridge case. In other words, it means that the case is 45mm long.

There are different names for them because 5.56x45mm NATO and 7.62x51mm NATO are the military designations for those rounds, where as .308 Win and .223 Rem are the civilian designations. There are a few other differences as well. For instance, the 5.56x45 NATO round and the .308 Win rounds are loaded to higher pressures than their counterparts.

The 7.62x54 is much different than the 7.62x39. The 7.62x54 is a rimmed cartridge that is 54 mm in length, while the 7.62x39 is not rimmed and only 39mm in length. These are two completely different cartridges. They were developed in the former Soviet Union.

 

[springmom]

Also, keep in mind that the U.S. is not on the metric system; so when the historic calibers were developed, they were numbered in terms of fractions of an INCH, not a meter.

But yes, .308 is not exactly the same as the metric "equivalent".

Springmom

 

[RLsnow]

oh god (is living in norway and is used to the metric system)

 

[DMK]

Also keep in mind that manufacturers or those that create the military specs on these rounds have not been exact in their measurements. It does get confusing.

For example:

7.62x51 (which is supposed to indicate a 7.62mm or .300 inch diameter bullet) uses a .308 inch bullet. 7.5x55 Swiss also uses a .308 inch bullet. 7.62x54R and 7.62x39 use a .311 inch bullet (.311 inches = 7.9mm). 7.7x58mm Arisaka uses a .311 inch bullet (7.7=.303). Oh and BTW, .303 Brit also uses a .311 inch bullet.

Handgun rounds are no better: .38 Special and .357 Magnum use the same .357 inch bullet. 9mm Luger uses a .355 inch bullet, 9mm Makarov uses a .363 inch bullet.


In fact reloaders can use the same .308 projectile for 7.5x55 Swiss, 7.62x51, and 30-06. They can also use the same .311 projectile for .303 Brit, 7.62x54R and 7.7 Arisaka. (7.62x39 uses a lighter projectile of the same diameter).

 

[RLsnow]

*is banging head into desk* No hablo english!!


seems there are alot of things i still dont know

i do know that Norway is phasing out the G3 7.62x54 for the HK 416 5.52 )

 

[macadore]

If you’re not confused enough by now, in the black power days, U.S. cartridges were designated by the bullet diameter in inches and the grains of black powder the case held. The 45/70 has a .45 inch bullet and the case holds 70 grains of black powder. When the U.S. and Britain went to smokeless powder, naming standards went out the window and the people who introduced new cartridges started giving the cartridges names like Enfield, Springfield, Webley, Special, ACP, Magnum, and so on.

 

[rcmodel]

In other words, it means that the cartridge is 45mm long.

Actually, it means the empty case is that long.

The loaded cartridge is much longer due to the bullet sticking out.


rcmodel

 

[Mortech]

LOl RLsnow , you mean phasing out the 7.62X51 Nato for the 5.56X45 Nato (lays a pillow on his desk )

 

[Regolith]

Actually, it means the empty case is that long.

The loaded cartridge is much longer due to the bullet sticking out.

Yeah, that's what I meant. I just used the wrong terminology. I'll go back and edit it.

 

[BobMcG]

Heck, they couldn't even keep things going in a sensible order back in the BP days.
Just when you see a pattern of bullet dia. followed by grains of BP followed by bullet weight IE: a popular .45-70Gov round of .45/70/500 and think it all makes total sense, there's a twist...
Yes, the .44-40 indicated a .44 caliber bullet with a charge of 40 grains of BP but the .38-40 meant no such thing. As most probably know, the .38-40 is actually a .40 caliber bullet but perhaps lesser known is that the original Winchester load for it was 38 grains of BP. Just backward of the .44-40.

(Of course one would have to slug a barrel on one of the old BP guns to determine the best dia. bullet for it's bore.)

 

[Fisherman_48768]

To further clarify: The 44 cal cap and ball revolvers are actually .451 to .457 or 45 cal. The 36 cal C&B were .375-.380 dia. The 44-40 or 44wcf actually uses a .427 dia bullet while the 44 spl and 44 mag use .429. Confused yet? Tell someone you want 45 cal handgun cartridges and see what you get.

 

[BobMcG]

Tell someone you want 45 cal handgun cartridges and see what you get.

You got that right. That'd be good for a strange look from the shop keep.

 

[Jimmy Newman]

Caliber is not a measure of the bullet diameter, at least in most modern cartridges.

The caliber actually has to do with the diameter of the interior of the barrel. Here in the United States, with the customary system, we measure the distance from one groove to the opposite groove, the largest measure of the barrel interior diameter. This is usually within a few thousandths of the bullet diameter. In Europe with the metric system, they measure from land to land, the smallest measure of the barrel interior diameter. 7.62mm does not equal .308", although both .308 Winchester and 7.62x51 use the same diameter bullets.

Also, some cartridges change the caliber measure by a thousandth or two just to be different from the other calibers that have the same barrel dimensions and use the same diameter bullet.

There are some other exceptions. For .38 special, .38" is the diameter of the brass.

 

[Fisherman_48768]

Jimmy Newman:

The caliber actually has to do with the diameter of the interior of the barrel...

You mean to tell me that I'm throwing a .429 dia bullet down a bore that is .440 cal in my 44 mag? Why does the 44 wcf use a .427 dia bullet? Both the 44 Mag and 44wcf are 44 cal.
Some mfg measure land to land, while others measure groove to groove and then some just give a nominal designation that sounds good.

I think that what everyone is trying to say is that there is no constant rule for cartridge designations.

 

[Jimmy Newman]

I did say there are some exceptions. In most cases it's the measure of the land to land or groove to groove diameter of the barrel. .44" may not be a barrel diameter, but it's not the bullet diameter, either (as you state, .44 is around .429 bullet diameter).

In a real technical sense, you could probably say that .44 mag is just a name for a cartridge and isn't actually .44 caliber, though .

 

[amprecon]

Here is a useful tool to use for conversion from english units to metric or vice versa http://www.onlineconversion.com/ here is another link to help with caliber sizes http://en.wikipedia.org/wiki/Caliber . This link will give you a visual comparison between the different cartridges http://en.wikipedia.org/wiki/List_of_rifle_cartridges

 

[trainwreck100]

The 7.62x54 is much different than the 7.62x39. The 7.62x54 is a rimmed cartridge that is 54 mm in length, while the 7.62x39 is not rimmed and only 39mm in length. These are two completely different cartridges. They were developed in the former Soviet Union.

My understanding is that the 7.62x54 designation is more commonly used for the American .30-06 (thirty caliber, formally adopted by military in 1906) whereas the Soviet's version is the 7.62x54r.

 

[Outlaws]

My understanding is that the 7.62x54 designation is more commonly used for the American .30-06 (thirty caliber, formally adopted by military in 1906) whereas the Soviet's version is the 7.62x54r

That isn't possible because the 7.62x51 (the 308) is not only 3mm shorter than the 30-06.

 

[Ian]

The metric size of the .30-06 is 7.62x63.

 

[BlindJustice]

One thing I haven't read is if the cartridge is
referred to as .223 Remington or 5.56x45 NATO
the latter is made to a certain specification for
military rifles whereas the former can be had in a
variety of bullet weights. Same with the .308
WInchester vs a 7.62x51 NATO - the NATO round
will be something like 165 gr. at 2,650 FPS I think
whereas a .308 Winchester can be had with bullet
weights from 110 gr. to 180 gr. in a variety of hunting
style bullets vs the NATO Full Metal Jacket aka FMJ.

 

[lee n. field]

there is 7.62x54 and 7.62x32(i think)

7.62x54 (old russian rifle round, been around since the 1880s, literally)

7.62x51 (old NATO standard)

7.62x39 (old commie standard)

7.62x25 (old commie pistol and subgun standard)

All of which are in current production and use. By the gazillion.

The metric size of the .30-06 is 7.62x63.

OOOp! There's another one!

Confused yet?

 

[Ian]

Also 7.62x45 (short-lived Czech cartridge for the VZ-52 rifle)
And 7.62x33 (aka .30 Carbine)
And 7.62x51R (European name for the .30-30 Winchester)
And 7.62x38R (7.62 Nagant, for the Russian revolvers)

 

[The Lone Haranguer]

Originally posted by RLsnow:
im confused about caliber stuff like

.223 is the same as 5.56mm
7.62 is the same as .308
there is 7.62x54 and 7.62x32(i think)

Caliber, technically, is the diameter of the bullet, or the inside diameter of the bore of the firearm. Particularly in America, the name of the cartridge is not necessarily -- or even usually -- the exact bore/bullet measurement. We also tend to use "caliber" as a synonym for "cartridge," saying the former when we really mean the latter. Some of your confusion may stem from this.

Addressing the particular questions in order:

1: Yes and no. The .223 Remington sporting cartridge (actual bullet diameter .224-inch) is the civilian version of the 5.56 (x 45) mm military cartridge. However, the two cartridges do not interchange. A .223 is OK to fire in a chamber/bore made for the 5.56, but not the reverse.

2: .308 Winchester vs. 7.62x51mm NATO, same notation.

3: The 7.62x54mm is a totally different cartridge. I've never heard of a 7.62x32 and presume you mean the 7.62x39. Both of these were/are Russian/Soviet military rounds.

3a: With metric cartridge designations, the first number is the caliber as described above, the second the case length (not the overall length with a bullet inserted).