Some help w/ ammo

[mrtopher39]

Im sure I will get hammered for asking what might be a really stuipd question but:
Can someone please explain ammo to me:
I dont get what a 5.56 / 7.62 / 9MM /.45 / 50 cal. / 30mm / refers to
Is it the bullet size meaing a 5.56 bullet is 5.56 mm long or is it the diameter of the casing? Is a 9mm round bigger than a 5.56? What is a 50 cal or .45 then?
I just dont get it.

Thanks for the help.

[Leopardi]

bullet width

[Chulo]

Yea, its abit confusing


a .22 is slightly smaller than a .233 but a .223 is nearly the same as a 5.56 (which is a .224) And the .22 can also be called the 5.6x15mmR.
Why? it is the .22 relates the the Bullet diameter, the difference is the metric vs. inch conversion
http://en.wikipedia.org/wiki/Caliber#Metric_versus_inch

[Bro Jangles]

Caliber is inches, so .50cal is half a ich, .45cal is .45 of an inch. MM is just that millimeter, so .50cal would be 12.7mm -ish.

[mrtopher39]

Holy cow chulo, that sounds almost like a tongue twister but thanks.

[mrtopher39]

So a 50 cal bullet itself is half an inch long or is it half an inch wide?

[Chulo]

So a 50 cal bullet itself is half an inch long or is it half an inch wide?
look at the chart http://en.wikipedia.org/wiki/Caliber#Metric_versus_inch

its apx .50 inch in Dia. a .22LR is over an inch long

http://img141.imageshack.us/img141/9857/riflecartridgecompariso.png (http://img141.imageshack.us/i/riflecartridgecompariso.png/)

[Bro Jangles]

So a 50 cal bullet itself is half an inch long or is it half an inch wide?
Wide, its not so much the bullet, it is bore diameter. now in a 7.62x39mm, the 39 is how long the round is.

[mrtopher39]

Oh I get it now: Another dumb question but a round is refered to as just the bullet or the entier thing casing and all?

[Chulo]

Oh I get it now: Another dumb question but a round is refered to as just the bullet or the entier thing casing and all?

Round


http://img267.imageshack.us/img267/9829/200pxcircle1svg.png (http://img267.imageshack.us/i/200pxcircle1svg.png/)


Bullet

http://img267.imageshack.us/img267/9488/180pxbulletsvg.png (http://img267.imageshack.us/i/180pxbulletsvg.png/)



A modern cartridge (http://en.wikipedia.org/wiki/Cartridge_%28firearms%29) consists of the following:
1. the bullet itself, which serves as the projectile (http://en.wikipedia.org/wiki/Projectile);
2. the case (http://en.wikipedia.org/wiki/Casing_%28ammunition%29), which holds all parts together;
3. the propellant, for example gunpowder (http://en.wikipedia.org/wiki/Gunpowder) or cordite (http://en.wikipedia.org/wiki/Cordite);
4. the rim (http://en.wikipedia.org/wiki/Cartridge_%28firearms%29), part of the casing used for loading;
5. the primer (http://en.wikipedia.org/wiki/Percussion_cap), which ignites the propellant.http://en.wikipedia.org/wiki/Bullet
Wikipedia is a good place to start for most questions (besides school)

[flanker7]

It has to also be said that nowadays the name of the ammo doesn't neccesarily matches it's excact dimensions.
So, a manufacturer may name it's ammo .224 but it actual dimensions be .2236
(fictional excample....)

[18SASS]

Round


http://img267.imageshack.us/img267/9829/200pxcircle1svg.png (http://img267.imageshack.us/i/200pxcircle1svg.png/)



Rounds are called rounds because at one time spherical balls were used in firearms. Today a 'round' is a complete assembly. How many rounds you loading? 30.





Wide, its not so much the bullet, it is bore diameter. now in a 7.62x39mm, the 39 is how long the round is.

You mean case length right? 39mm?

[Bro Jangles]

You mean case length right? 39mm?
yes the casing is 39mm

[Dean1962]

Calibre sizes get even weirder the more that you look into it. Many bullets with identical calibres are different, due to the fact that some of them used the calibre of the bullet, while others used the calibre of the weapon barrel. Yet others measured the barrel calibre from land to land, while others measured from groove to groove. Still others rounded the number off! In fact, there is no universal agreement on bullet measurement, or even on casing measurements for that matter. As an example, many people believe that 7.62x51 NATO is the same as .308 Winchester. In fact, they are not. 7.62 NATO has a higher shoulder and is virtually always made with thicker brass, resulting in a lower powder capacity. All in all, cartridges, bullets and weapons are a very strange world.

[Migs]

and dont even start with shotgun gauges....


An n-gauge diameter means that a ball of lead (density 11.352 g/cm3) with that diameter weighs 1 / n pounds (453.59237 grams). Therefore an n-gauge shotgun or n-bore rifle has a bore diameter (in centimeters) of approximately
http://upload.wikimedia.org/math/9/a/e/9ae6aae9f93f01c229c72003011a1ede.png

feel bad for the guy who had to make that
im terrible with equations

[Dean1962]

Wide, its not so much the bullet, it is bore diameter. now in a 7.62x39mm, the 39 is how long the round is.

Actually, the 39 refers to the length of the casing.


Are you suffering from information overload? If so, this is merely another instalment.

[Bro Jangles]

Actually, the 39 refers to the length of the casing.


Are you suffering from information overload? If so, this is merely another instalment.
actually if you read down, i corrected myself.

[Dean1962]

actually if you read down, i corrected myself.

Quite right, you did. The funny thing is that when I wrote the correction, a few posts, including yours, were nowhere to be seen. Sorry 'bout that. My correction stands corrected.

[Jippo]

Calibre sizes get even weirder the more that ... As an example, many people believe that 7.62x51 NATO is the same as .308 Winchester. In fact, they are not. 7.62 NATO has a higher shoulder and is virtually always made with thicker brass, resulting in a lower powder capacity. All in all, cartridges, bullets and weapons are a very strange world.


Consider caliber names as names only and it will be simple.

Only time you need to know the actual exact dimensions is when reloading. And for that it is sufficient to use e.g. mm dimensions then: just buy bullets with correct diameter, use cases with the right "name" on them and check exact ammunition dimensions from C.I.P specs.

In case of .308Win it doesn't matter if the round is called .308Win or 7.62x51 NATO. For the differences in dimensions are so small that it makes no difference in practice. 7.62x51 NATO rifle can shoot civilian .308 ammunition and vice versa.

[Dean1962]

Consider caliber names as names only and it will be simple.

Only time you need to know the actual exact dimensions is when reloading. And for that it is sufficient to use e.g. mm dimensions then: just buy bullets with correct diameter, use cases with the right "name" on them and check exact ammunition dimensions from C.I.P specs.

In case of .308Win it doesn't matter if the round is called .308Win or 7.62x51 NATO. For the differences in dimensions are so small that it makes no difference in practice. 7.62x51 NATO rifle can shoot civilian .308 ammunition and vice versa.

Quite true. I was simply pointing out that there is a quantifiable difference between two "identical" rounds. That being said, the difference causes two problems for a very few shooters. People who have 7.62 rifles and buy, then reload their brass find that .308 brass stretches far more than 7.62. As for shooting it, there should be no difference at all, unless you are using .308 ammo in a sub minute of arc sniper rifle. if there is uneven deformation of the brass, it could conceivably cause the bullet to be released too soon or too late, or throwing it a bit off. I know of only one person who complained of it, (he was a Canadian Forces sniper who bought and used .308 match ammo in a Parker-Hale 7.62 sniper rifle) and he always said that he had more trouble hitting long range targets with .308. OTOH, it also depends a lot on your rifle.

[Sabre]

I still find american measurements amusing.

Firstly it's the 'Imperial' system, ie the Empire you fought a war to leave. Secondly, you're virtually the only country still using it.
Thirdly (in this case), surely a half inch calibre should be expressed as 1/2", using imperial notation, not 0.50 ie using a metric decimal expression? So a .45 cal would be a 9/20" cal?

Bonkers...

[mrtopher39]

Man I feel dizzy after reading all of this. How does anyone make sense and keep track?

[Jippo]

Man I feel dizzy after reading all of this. How does anyone make sense and keep track?

Easy.

If a barrel of my rifle says .308Win stamped on it, I can go to a shop and by a cardboard box that has the same magical letters on it. That is all there is is. IF someone wants to step out and learn more they can, but they don't have to.

If there is an issue like: can I use 7.62x51 in my rifle which is .308? Do not do it if unsure, if sure you can, then by all means do it. But that is already higher level of guns & ammo, not needed to know if not interested on the matter.

No point in trying to make sense and keep track of all the calibers, there are too many. People even make their own calibers by modifying existing brass. And nothing stops them naming them .406x57 Donnerundblitzen if they like to do so.

[mrtopher39]

Hey, thanks so much for the info. Its great knowing I can count on the members (like you) for answers.

[Dean1962]

I still find american measurements amusing.

Firstly it's the 'Imperial' system, ie the Empire you fought a war to leave. Secondly, you're virtually the only country still using it.
Thirdly (in this case), surely a half inch calibre should be expressed as 1/2", using imperial notation, not 0.50 ie using a metric decimal expression? So a .45 cal would be a 9/20" cal?

Bonkers...

I would tend to agree, except for the fact that it was the British who invented the calibre system, and many of the cartridges that came with it. .303 Enfield springs to mind! And let's not forget all of those wonderful Martini-Henry calibres or the Webley Pistol cartridge.p-)

But I ca laugh at both of you. I'm Canadian;)

[California Joe]

Now tell him about the cartridges like .257 Roberts and .222 Fireball...:)

[18SASS]

Now tell him about the cartridges like .257 Roberts and .222 Fireball...:)

7.62 lazzeroni warbird too.

[Chulo]

Damm this must be the smallest bullet out there. Used to shoot down attacking killer bees
2 mm Kolibri


http://en.wikipedia.org/wiki/2_mm_Kolibri
http://img9.imageshack.us/img9/7522/kolibriadamsguns.jpg (http://img9.imageshack.us/i/kolibriadamsguns.jpg/)



The cartridge weighed 5.3 grams (82 grains) , measured 3 millimeters (0.12 in) at its widest point, and 11 mm (0.43 in) from the base of the primer to the tip of the bullet. The bullet itself weighed 0.2 g (3 grains), and was estimated to have a normal muzzle velocity of 200 m/s (650 fps), resulting in a muzzle energy 4.0 joules (http://en.wikipedia.org/wiki/Joule) (3 foot-pounds (http://en.wikipedia.org/wiki/Foot-pounds)).

[Migs]

you're virtually the only country still using it.
cuzz its american and that means its the best dawg *noms apple pie*

[Dean1962]

cuzz its american and that means its the best dawg *noms apple pie*

Not in the least. It simply means that the US is still manufacturing cartridges and labelling them with their inch measurement rather than the metric equivalent. The nice thing about the metric system is that you immediately know exactly which cartridge is being used whereas the inch system leaves a lot of doubt. There are many .30 calibre cartridges out there, and if you refer to one as .30 calibre, I have no idea what you are talking about. Another example is .338. There are at least six .338 cartridges that I know of off the top of my head, and I don't know which one you are talking about unless you use the name. (.338 Winchester, .338 Weatherby....) But if you say 8.59 x 71 mm, I know exactly what you are talking about. (.338 Lapua!)
Otoh, many countries that use metric are still using the old label for well known cartridges. Canadian manufactured 7.62 x 63 mm ammunition is still labelled 30-06, because everyone still calls it that. Really, it depends on the manufacturer as well as the cartridge in question. However, most new cartridges do have a metric label, except in the US.

[Consigliere]

Easy.

If a barrel of my rifle says .308Win stamped on it, I can go to a shop and by a cardboard box that has the same magical letters on it. That is all there is is. IF someone wants to step out and learn more they can, but they don't have to.

If there is an issue like: can I use 7.62x51 in my rifle which is .308? Do not do it if unsure, if sure you can, then by all means do it. But that is already higher level of guns & ammo, not needed to know if not interested on the matter.

No point in trying to make sense and keep track of all the calibers, there are too many. People even make their own calibers by modifying existing brass. And nothing stops them naming them .406x57 Donnerundblitzen if they like to do so.

Funny you should mention the .406x57 Dunderundblitzen (sorry to correct your spelling) - that is my Elk rilfe, and I used it this year to fell a big one!

Put a scope on it and it and it is Thunder and Lightning man! (With a 1903 leather sling, of course!)

C.