Calibre of a weapon | Some questions around it

[gverma]

I have understood the meaning of the Calibre of a weapon from this link http://en.wikipedia.org/wiki/Caliber
I believe I understand what is meant by .22 and the difference between 0.32 and 0.32-60 (assuming such exists)

My questions are as under

1. When we say a gun will use .22 calibre bullets can I use any companies 0.22 bullets or am I locked in by the rifle maker, in other words even after standardization are rifle makers allowed to make some small changes so as to have some kind lock in

2. Lets take example of IOF, the make 0.22 revolver and 0.22 rifle would this mean that the same bullet can be used in both the guns or there is a variation of the bullet even in same calibre between gun types.

Thanks
Regards
Gaurav

[bruceissippi]

Using the US cartridges as my examples - a .22 Long Rifle, .22 Long, and .22 Short use a bullet with a diameter of .222 inches, the .22 Winchester Rimfire Magnum and the various .22 center-fire rounds use bullets with a diameter of .224 inches except for the .22 Savage Hi-Power which uses a .227.

Looking at the IOF website is not real helpful, but it appears that both the .22 rifle and revolver are for the .22 Long Rifle rim-fire.

All makes of .22 LR ammunition that I have seen - US, South American, European, and Russian - are manufactured to the same dimensions so any of them should work in these guns. That said, I've found that .22s can be very picky as to which ammunition they will shoot well. I get a small amount of every kind I can obtain and try it in each gun. Then, I get as much as I can afford of whatever shoots the best.

[Amit357]

Hi Gaurav,the caliber of the ammo is a measurement of the dia of the projectile it fires,in some countries its in MMs and in some its in parts of inches.22 is a good example of the same,22 being the part of inch and 5.56 mm in the MMs,22 come in various diamesions like 22 LR,long short these being Rimfires,then the centerfire 223,22 Hornet,22 swift,22-250.There is a conversion table you can Google it.
As far as IOF goes,its basically a 22 Long Rifle or 22 LR the most common one,for IOF 22 Revolver stay with Eley Tennex only,KF ammo will jam { it usually does because of exellent quality control by IOF },in the revolver,and dont use Hi-Velocity ammo like CCI,Winchester Super X etc in it.The IOF 22 rifle is less problematic with ammo,you can use most of the ones availble here in it from CCI Stingers to Lapua etc,etc,try and avoid IOF ammo.A small tip with the rifle,after firing,pick up the bolt, push the bolt a little ahead and pull it back to eject the spent case from the chamber,dont just pull it back.The extracters are a little brittle and do wear out after some time if you pull the bolt staight out after firing.All the best
PS there is an article,Cornered Cat,Caliber Confusion by Kathy Jackson,it will give you a general idea on caliber,check it out

[Anand]

Boy o boy, Amit did you open a can of worms . The most confusing thing about ammunition is the caliber and the names of . Just to give you an example & confuse you some more :
1. .32 S&W & .32 Winchester Special are not interchangeable the first is a handgun cartridge while the latter is a rifle cartridge.
2. .22 LR is a rimfire & .22 Hornet is a center fire cartridge. Both are not interchangeable.
3. .38 S&W Special cartridge can be chambered & fired in a .357 Magnum caliber Revolver
4. 30-06 is the name of a rifle cartridge that has a bullet diameter of .30" and was designed in 1906.
5. 7.65 mm pistol cartridge(.32 ACP) is not the same as 7.65mmP (which is a bottle neck cartridge also called a .30 Luger)

Basically what I am saying is that the name given to a cartridge is not dependent on the true diameter of the projectile as in a .30-06 ( projectile usually measures .308") or a .32 S&W (projectile usually measures .312"). Also the second half of the name may either be the year it was introduced as in 30-06 or the powder charge as in .32-20( the '20' being the weight in grains). A .38 Special projectile and a .357 magnum projectile both measure .357". In European cartridges the second half of the name is usually the lenghth of the case as in 7.62x25mm.
I could go on and on but you get the idea!
Regards,
Anand

[MoA]

As long as the weapon is chambered for .22LR, you can pretty much use any .22LR ammo in it.
Will caveat the use of stuff like stingers, and velocitators in guns made over a 100 years ago. Other than that go forth and shoot.

[maximus]

Its the bullet dia. .22 but the shell size may wary from 22Long to .22 short to .22 LR to 22 WMRF. but our IOF .22 rifle /revlover takes the .22 LR cartridge and both the firearms are compatible.

Maximus

[timmy]

Gaurav:

When you see a cartridge designation, my advice to you is to study it before drawing conclusions. Usually, a cartridge name will give you a rough idea, but seldom a concrete idea about what you are really dealing with.

For example, look at these pistol and revolver rounds:

.380 ACP
.38 Colt Super
9mm Makarov
9mm Parabellum
.38 Special
.357 Magnum

All of these use ABOUT the same size bullet, but the differences are such that you should take a really close look at what's up.

In the case of the set of cartridges I've listed, note:

.380 ACP, .38 Colt Super, and 9mm Parabellum all shoot a 9mm bullet, which is generally considered to be for a .355" bore -- when measured groove to groove (which is also a source of confusion!) The 9mm Makarov, while called a "9mm," uses a bullet that's .363"/.364" in diameter. In other words, the bullets themselves are not interchangeable between the first three cartridges and the 9mm Makarov.

Now, oddly enough, here's the .38 Special and the .357 Magnum: they both shoot the same bullets! Why the different names? Well, if you study a .22 Long Rifle cartridge, you will see that the bullet and the cartridge case are the same diameter. There's a part of the bullet, called the HEEL, that is inside the .22 cartridge case. That's why it is said that .22 LR has a "heeled bullet." These bullets must be outside lubricated. The .38 caliber revolver rounds (and the .44 caliber as well) used to be made like the .22 LR, and the bullets for them were a true .38" in diameter.

But outside lubricated bullets are messy. If you carry them in your pocket, they pick up fuzz and dirt, and they leave grease behind. (.22 LR doesn't do this with the most modern types of bullets, because newer lubrication types have been developed to get around this problem. However, in more powerful revolver cartridge bullets, those kinds of lubrication aren't so effective.) So, to get an inside lubricated bullet, the whole bullet was made to the same diameter as the inside of the cartridge case. This made the bullet smaller, and lubricant could be carried by the bullet in grooves inside the case. No more mess!

But then, the bullet was no longer .38" in diameter. When the .357 was developed, it was a lengthened .38 Special cartridge case that operated at a higher pressure, and the cartridge designation reflected the newer bullet size, not the original parent cartridge's.

Colt made two .41 caliber revolver cartridges. They tried to make inside lubricated bullets without a heel by making the bullets with hollow bases. Then, the bullets would be about ..386" or so in diameter, and when they were fired, the hollow base would expand to fit the .41" bore. This is how the old Minie Ball musket bullet worked. Colt thought that this would enable the older guns to shoot the new ammunition with inside lubricated bullets, but the hollow base bullets are harder to make and generally less accurate.

Another thing was that, when Colt went to making .38 caliber revolvers, they used a .354" bore diameter, not the .357" that Smith & Wesson used, and which is generally accepted today (even by Colt!). So, in my old Colt .38 Special revolvers, I have to shoot cast 9mm pistol bullets that generally are sized at .356", because a .357" or .358" bullet is too large for the bores of these older Colts.

So, you can get a general idea: all of these cartridges shoot bullets that are about the same diameter and will have about the same performance at the same speed and with similar design. Beyond that, you have to study the details, because (for instance) a 9mm Makarov and a 9mm Parabellum are most certainly quite different, even though they may sound the same.

With rifles, it is the same thing. A .30-'06 shoots a .308" bullet, same as a 7.62x51mm NATO cartridge (and we call it .308 Winchester here). However, there's also a 7.62x54r Russian military cartridge, and it shoots a .310" to .312" bullet, same as the .303" British service round. Again, you have to do a little more work to figure out what's what.

I could go on forever about this subject, a fact that illustrates that cartridge names can often be misleading, depending on what you are using the name to indicate. I suggest that you approach the subject on a cartridge by cartridge basis.

Do a lookup of each cartridge you are interested in on the internet. Like any other subject, there is a lot of bunk on cartridges on the internet, but there is also a lot of very good and useful information. Also, you can always ask here at IFG. There are people here who can give you good information and advice.