"Caliber" = misnomer

Redleg

Just have to clear the air here. Most of you may not know, but to say that a 30-06 or 30-30, or whatever is a particular "caliber" is a misuse of that word."Caliber" is defined as the length of the tube (barrel) divided by the diameter (bore).I am an artilleryman and we use these words all the time. Modern 155mm bore-diameter cannons (M-109A6, M-198) are 39 calibers. Do the math and you will know that a 39 caliber 155mm cannon is 6.045 meters long.Why am I saying all this? Dunno. I'm at work and bored out of my mind. Seriously, the caliber of a weapon affects its internal ballistics (muzzle velocity, etc.)Hope y'all see the light and start using the right terminology! Brian

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Crush your enemies, drive their horses before you, hear the lamentation of their women.--Genghis Khan

concealedG36

Thanks Redleg. But now you need to tell me what .30-06 or .30-30, etc. are called. If these are not calibers, then what are they? (I'm not disagreeing, I'm just asking)G36

Lowrider

That may be the military definition of "caliber", but Webster's defines it as:1.The diameter of a bullet or other projectile.2.The diameter of the bore of a gun, usually expressed in hundredths or thousandths of an inch and usually written as a decimal fraction.[This message has been edited by Lowrider (edited 10-03-2001).]

Redleg

Lowrider,I know that's what the general populace uses (including me) for the meaning of the word, I thought I'd throw out an alternative. The Navy uses calibers as I have described like the 5"/54 gun, which is a 5 inch, 54 caliber gun.BTW, a gun is not a howitzer, but both are cannons. A gun is usually a flatter trajectory weapon while a howitzer has a more lobbed trajectory. (FYI)G36,.30-'06 is a .30 inch bore diameter bullet that was designed for the military during the year 1906 (hence '06). Same applies for the .30-'30.I think there is a different convention for old government bullets like the 45/70 (if I am correct is a .45 inch diameter bullet in front of 70 grains of black powder) If that's wrong, somebody help me out!

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Crush your enemies, drive their horses before you, hear the lamentation of their women.--Genghis Khan

bfair

My 2 cents on 30/30 30/06.The first number is the caliber. However 30/30 is really .307 and 30/06 is 308.the second number comes from black powder day and relates to case capacity 30 gr of black powder. 45/70 70 grs of black powder

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Semper Paratus [This message has been edited by bfair (edited 10-03-2001).][This message has been edited by bfair (edited 10-03-2001).]

leeblackman

I don't call the 30-30win and 30-06spr calibers, if I refer to them they are .30cal's, instead I refer to them as Cartridges as most ammo manufacturers do.Did you know if you were from Britain you would spell caliber, calibre....Remeber Cartridges, not calibers. A calibers is a mesurement under an inch, .30 caliber is .3" or 3/10 of an inch if I'm not mistaken.

32wsl

Redleg, take a look at Webster's. I believe that book is the authority on definitions.

Xracer

.....and 25/06 is a 30-06 case necked down to 25 caliber, and .38 Special is .357, and 45/70 is 45 caliber and 70 grains of black powder, but 38/40 is 40 caliber and 38 grains of black powder....and 250/3000 is .250 with a 3000 fps muzzle velocity.....and if you're not confused, you obviously don't understand the situation........

Lowrider

RedLeg: A buddy of mine was assigned to a track-mounted artillery piece during the Viet Nam war. They just drove it around like a tank, but he'd get pissed if you called it that. "It's not a damn tank," he'd shout. I think it was a 155mm gun. What do you know about them?

spclark

So my Ruger Deerfield or Super Redhawk aren't .44 Remington Magnum CALIBER, but are instead CHAMBERED for .44 Remington Magnum?

Redleg

Lowrider, Did it look like this? If so, that is an M-109A6 155mm howitzer, and it's not a damned tank!!! (ha, ha, ha) I spent 4 years on these buggers and the last 2 on towed 155mm howitzers. I know everything there is to know about them.

Redleg

Spclark,You are correct! The old usage of the word caliber (and still in use today by the Navy, Marines, Army, and Air Force is length divided by bore diameter.However, it's become very convenient to call a .44Mag a 44 magnum caliber. I just thought I start setting the record straight! Brian

Lowrider

RedLeg: I never saw his gun in the flesh, but that sure looks like the pictures he showed me. How many men on the gun crew??

Redleg

The new M-109A6 has a crew of 4 people: Section chief, driver, gunner, and number one man. The gun can carry 39 projectiles including 2 guided Copperhead munitions. It has a maximum range of 30 km with rocket assisted projectiles and Charge 8-Super. it has an "in-place-ready-to-fire" time of 30 second (vs. the average of 10 Minutes for the old system). What a gret piece of gear, but a pain in the butt to fix when it breaks!

opentop

Regardless of what the word caliber originally meant, today it refers to a measurement in 100ths of an inch, primarliy used to measure the diameter of firearm projectiles or bullets. Anything can be measured in calibers if you so desire. It's pretty much just like any other degree of measurement. 38 caliber is 38/100ths of an inch. Although, often calibers named are not their true size. For example, 38Spl actually has a true measurement of .357 inches or 35.7 calibers and 44Magnum is really .429 inches or 42.9 calibers. On the other hand, .40S&W is exactly .4 inches or 40 calibers, as is 10mm which just happens to be the metric measurement of the same sized bullet. Interestingly, 25MM is exactly one inch or 100 calibers. The thing I always wanted to know is why everybody and his brother over the years always came up with their own cartridges all the time. I can understand that back in the later half of the 19th century when the self-contained metalic cartridge was coming into prominence, that each gun maker usually developed his own cartridge which he felt would be best suited to the weapon he was designing, but after that, you'd think gun makers could have put their heads together and standardized some basic sizes. Also, why all the "odd" sizes and why were they often misnamed? For example, why did people in Europe who have used the metric system for some time now, bother with the 9.37MM and 8.7MM, etc. Or another one, why when developing the M16, did they come up with 5.56MM. Why not just an even 6MM. I understand 7.62MM because that's just a metric rename of a 30 caliber round but when you're developing a whole new gun and a whole new cartridge, why not come up with a nice even number?

bfair

and....Naval guns are Rifles as they are not smooth bore and the Marines we hauled around in 'Nam had 8" self propelled guns.Just refered too a 8"ers

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Semper Paratus

Redleg

Opentop,Caliber (to people who study how rifles work and what ballistics are) still means length of the tube divided by its bore diameter. Caliber is a normalization of the dimensions of a rifled barrel, that, to a ballistics engineer, will clue that person in to the performance of that particular tube.A carbine, for instance, is a short-caliber rifle.The reason the Europeans use metric measurements is that they are strictly describing the bore diameter, not the caliber of the weapon. A 7mm is not a 7mm caliber. A 7mm is a 7mm diameter tube with a length "x". A 7mm, 10 caliber weapon is a 7mm tube with a 27.5 inch long barrel. A 7mm, 8 caliber weapon is a 7mm tube with a 22 inch long barrel....a completely different weapon.

Redleg

From FM 6-40 "Field Artillery Manual Cannon Gunnery"Caliber: An expression of the length of the tube obtained by dividing the length from the breach face to the muzzle by the inside diameter of its bore. A gun tube with a bore 40 feet long (480 inches) and 12 inches in diameter is 40 calibers long.

JudgeColt

I always try to use "chambering" when describing a particular firearm offered in more than one cartridge designation. It is a bit like someone saying "I am going to buy some bullets" when he means he is going to buy some cartridges. Common usage often ignores the correct usage.

whiteclouder

The term caliber can and is used to describe the inside diametric measure of a cylinder, be it a blood vessel or hypodermic syringe. As such, it is used to describe, in inches, the size of a rifle or pistol bore. And just to muddle things up, they use increments of 1/100. The Europeans on the other hand simply specify metric units throughout for both bore diameter and case length. They started simply with 7,8,9,10,11,12 and 13 MM. The odd sizes came later as they copied and described our English units. Advertising and sales for the most part drove the manufacturers to differentiate their brand of a particular caliber from another, for instance 38 Long Colt and 38 S&W, or 300 Savage and 308 Winchester. Both used .357 and .308 caliber bullets respectively but you had to trust the manufacturer meant well by designing a different shape and even type of case. And as has been pointed out the caliber does not have to describe the actual diameter of the bullet. A 22 caliber can be anywhere from .223 to .228 and be so nearly identical in performance as to be ludicrous, 223Rem and 222RemMag or .243 Win and 244 Rem, now really. NATO politics drove the 5.56 designation as well as the 7.62In the case of the artillery pieces, they measure the length of a barrel with the rather obtuse term of caliber, which in this case would be an arbitrary term, obtuse and arbitrary, now that's real military for you. It comes from the ballistics requirements. They have figured that a given projectile diameter requires a certain minimum length of tube to perform efficiently and from this you get Redlegs' correct ascertain.The navy also uses the caliber as a unit of measure but they describe the caliber in inches and then give you a numeric factor to derive the length of the gun. Can't allow the navy to do anything like the army, now can we? At least the military system is a constant.Call the cartridge what you will, 577 T'Rex to a 22 Cheetah. You just have to know what it means, you certainly can't glean anything intelligent out of the designation.Clouder..

opentop

Redleg - I agree with Whiteclouder and stand by my original reply. "Caliber" while it may originally, in naval parlance been a measurement of length of barrel divided by bore diameter, is now accepted almost universally by gun aficionados and others, as a unit of measurement in hundreths of an inch. The part in my earlier reply about the various size names, etc., was meant mostly facetiously, by the way.

s.gun

I drive on the Parkway.I park on my Driveway.I get confused at times.

SP Tiger

When my wife and I toured the U.S.S. Alabama two years ago, I was floored when I saw this huge naval shell that was as tall as I am and it was labeled as being "45 Caliber". There was another marked "38 Caliber". It really blew my mind. I had to do some research on that one to make sure I wasn't just dreaming.

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Better to have and not need, than need and not have.

He Dog

Caliber seems a useful convention to describe the diameter of the bore or projectile in hand guns and rifles. My favorite .257 Roberts will always be .257 inch in diameter, but its caliber will change depending upon whether the barrel length is 22" 24" or 26" Hardly seems useful to discuss the caliber of my rifle in those terms. If someone asks what caliber do you shoot and I reply .257 Ackley Improved they know what I mean. The barrel length I prefer or got stuck with is a separate issue. Besides, that thing looks like a tank to me.

bfair

When you buy a box of bullets for reloading.It says Caliber on the box. ie 38/357 357 dia. Not one word on barrel length.

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Semper Paratus

opentop

And afterall, we're not all in the Navy.

Xracer

SP Tiger....that 45 caliber would have been a shell from a 16"/45 cal. main battery. The Alabama carried 9 of these....two triple turrets forward, and one aft. Each fired a 2000 pound projectile a distance of 18-21 miles (depending on the powder charge) and could drop it in your pocket.The 38 caliber was from a 5"/38 cal. secondary battery.