shotgun and rifle ammo meanings?

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countryboy281

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could someone explain to me how shot gun and rifle ammo is categorized im new to the whole rifle and shot gun world ive been hooked on compound bows forever and have owned a 270. but other than that its been hand guns. some one please fill me in thanks.
 
In a word, no.

Shotguns often use an antique method of powder measure called Dram equivalent (which really needs to go away). Here's a good article on shotgun information - http://en.wikipedia.org/wiki/Shotgun_shell

Rifles are essentially either centerfire or rimfire. In centerfire cartridges the designation can either be in caliber (thousands of an inch, such as .270), or in millimeters shown as mm. That might seem simple enough, except that some cartirdges have their caliber designation based on the groove diameter, and some are designated based on land diameter.

A .243 Winchester and a 6mm Remington actually use a .243 diameter bullet, but your .270 doesn't use a .270" bullet. It's actually a .277" bullet, in millimeters it's a 6.8mm. But it has absolutely nothing at all to do with the 6.8 Remington SPC cartridge (which also uses 6.8 mm (.277") bullets.

Lot's of info available on the web though, try google and you;ll come up with many days of reading.

Pistols are much worse, with the nomenclature assigned to the cartridge sometimes having absolutley nothing to do with the nominal caliber, such as a .38 Special (whihc has a groove dimater of approximately .357").
 
I agree with browningguy, the dram measurement needs to go away. That was used way back when all you had was black powder. It was a hold over since everybody knew what that measure was. It has just perpetuated itself decade after decade.

I'm glad I don't handload rifle, I have enough on my plate with pistol and shotgun....lol
 
Don't forget the nomenclature related to case length like 7.62x51 vs 7.62x54r, etc. It's pretty involved, start googling different cartridges that interest you and you'll learn a lot of the terminology that way.
 
There are tons of variations in cartridge names. The .30-06 springfield is .30 caliber and was adopted by the US govt in 1906. The .30/30 was initially loaded with a .30 caliber bullet over 30gr of black powder. Then you have the various .44 calibers, which are actually .43 caliber, and the .38's which are .357 projectiles. The .250/3000 savage (which uses .257 bullets) was the first commercial cartridge to break 3,000 fps. You could just about write a book on the subject.
 
... and we haven''t even discussed the crazy almost obsolete ammo, .450 x 1 1/2", 450/400 NE, then rimmed and rimless (ie 7x57 and 7x57 R) etc.

If you look at wildcats it gets worse. Something simple like a .223 Remington case necked up to .243". I've seen it called the 6x45, 6-.223, and now someone has another name the .243-.223, as if they are inventing something new.
 
Do like I did 45 years ago. Buy cartridges of the world and read it so much the pages fall off. Then buy a new one.
 
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There are tons of variations in cartridge names. The .30-06 springfield is .30 caliber and was adopted by the US govt in 1906. The .30/30 was initially loaded with a .30 caliber bullet over 30gr of black powder. Then you have the various .44 calibers, which are actually .43 caliber, and the .38's which are .357 projectiles. The .250/3000 savage (which uses .257 bullets) was the first commercial cartridge to break 3,000 fps. You could just about write a book on the subject.
The .30-30 was initially loaded with a .30 cal. ie; .308 bullet over 30 grains of early smokeless powder............
 
Correct. The .30-30 WCF was developed with smokeless powder, not blackpowder. 160gr bullet with 30gr of smokeless powder (approximate equivalent to IMR 4064) and a muzzle velocity of 1,970 fps in a 26 inch barrel, though advertised as 2,000 fps.
 
Welcome to THR countryboy281

First off, this can be very confusing. There is no standardized system for naming a cartridge, that would be too easy. I tend to lump them all into 1 of 3 categories:

Metric: Probably the best system IMO, because it will often give you both the bullet diameter and the case size in the cartridge name. Example, 7.62x39 is a bullet diameter of 7.62mm (.30 caliber) in a case that is 39mm long. Metric will usually tell you if a case has a rim or not too, buy putting an "R" at the end of the name. An example would be 7.62x54R

Old Standard: These cartridges consist of 2 numbers, the first being the bullet diameter and the second being the power weight for the charge, in grains. .30-30 is the most common, a .30 caliber bullet with 30 grains of powder as the propellant. There are many others as well, .45-70, .30-40, .44-40, etc.

New Standard: Usually this consists of just the bullet diameter and the name of the company that created it (or standardized it from a wildcat). Example, .280 Remington is a .28 caliber (7mm) bullet that was standardized by Remington. While this is the most common name standard that you'll likely run into, I actually like it the least because it gives you very little info on the cartridge without having to do some research.

Of course there are some oddballs that don't always fit well into one of these 3 types, but they're the most common by far. And that's just for rifle/pistol. Shot shells are a whole different thing.

With shot shells, smaller = bigger. A smaller "gauge" is actually a larger shell. Example, the 20ga is actually smaller than the 12ga. The same thing is true for pellet sizes, a #7 pellet is actually smaller than a #4 pellet. So the general rule of thumb is that everything is backwards.

There are really 3 things to look for in a shot shell:

Gauge: This is the diameter of the shell. Most common are 12ga and 20ga, but there are several others.

Length: Some shells are longer than others. The standard is 2.75 inches, but some shells are as long as 3.5 inches. The barrel of your shotgun should tell you how long of a shell you can use.

Pellets: Again, smaller is bigger. Also pellets are broken down into 2 groups, birdshot and buckshot. Birdshot is much smaller and good for shooting clay targets or bird hunting. Buckshot is larger and is better for personal defense. Despite the name, I don't know anyone who hunts deer with buckshot. You can buy shot shells that have a single large projectile, they're called "slugs". If you hunt deer with a shotgun, you probably want to be using slugs.

Hope this helps... but probably just makes it even more confusing...
 
Shotgun gauge designation is, if I remember correctly, the count of the number of round lead balls, of bore diameter, that will make up one pound. It takes 20 of the smaller 20-gauge balls to make up a pound, but only 12 of the larger 12-gauge balls to make up a pound.

etc . . .

A fairly accurate way to translate mm designation into inch/decimal designation, is to multiply the mm number (i.e. 7 mm) by 4; 7mm = 28 caliber. You can, of course, do it backwards as well -- 50 caliber is 12.5mm. More or less.

etc . . .
 
AntiSpin said:
Shotgun gauge designation is, if I remember correctly, the count of the number of round lead balls, of bore diameter, that will make up one pound. It takes 20 of the smaller 20-gauge balls to make up a pound, but only 12 of the larger 12-gauge balls to make up a pound.

AntiSpin is correct, the only exception is the .410 which is a the bore diameter in thousandths.

Another fly in the ointment is that some calibers were measured land to land, others were groove to groove.
 
And the 30wcf also known as 30-30 is also sold as 7.62x51R, not the same as 7.62x51, 7.62x51 nato, or 308 Winchester. And 7.62x39 is .311 dia, all others listed here are .308. Also 30 carbine is .310 dia but all are considered 30 cal.
 
And the 30wcf also known as 30-30 is also sold as 7.62x51R, not the same as 7.62x51, 7.62x51 nato, or 308 Winchester. And 7.62x39 is .311 dia, all others listed here are .308. Also 30 carbine is .310 dia but all are considered 30 cal.
Actually the 7.62x39 & the 7.62x54R is .312 ie 7.92 & the .30 carbine ie;(7.62x33) is .308.............
 
According to Modern Reloading By Richard Lee the 7.62x39 bullet dia is .311. You are right I messed up on the 30 carbine, the cast I use is .310. The bullet is.308. I did not mention the 7.62x54R, but the same book lists the bullit dia. as .310.
 
So a quick question, that a previous posted simply hinted at.. What is a "Wildcat" cartridge?
 
"Also, American cartridge/caliber naming seldom corresponds to the actual bore diameter. This is something you pretty much have to pick up as you go along."

All too true, sadly; one very good example is the whole .36 caliber / 9mm family.

All these cartridges -- .380, 9mm, .38 Special and .357 magnum (and some others as well) are really .36 caliber; that is, the bullet diameter is .356" ~ .358".

There was a revolver -- don't know if it's still made or not -- called the Medusa, which somehow could chamber and fire all the .36 caliber rounds, both rimmed and rimless.

Never saw one, so I don't know how they accomplished that, but it was an impressive feat.
 
And caliber may also be the ratio of the barrel length to the projectile diameter.

Here's a 52 caliber rifle being loaded with powder bags:

bb-61-DNSC9103644_JPG.jpg


Sixteen inch bore, 52 caliber, means the barrel is 70 feet long. The red line on the wall indicates how far back it will recoil.

Then there's "lines." That was used for a while to indicate bore or bullet diameter in Russia, where a "line" was one-tenth of an inch. Thus, a three-line rifle meant a .30 caliber.

Well, that's the way I heard it, anyhow.

Just to add to the confusion.

Terry, 230RN

REF:

http://findarticles.com/p/articles/mi_m0BQY/is_11_52/ai_n16741375/
 
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