Vever have on a 22mag bur Ruger combo revolvers are. The bore of 22WMR and 22 rimfire are different. The former has a .224 bore, the later .222. Always knew this but never knew why they would do this & why both wouldn't be standard.

 

flylo is correct in that the 22 WMR and 22 LR use different groove (and bore) diameters, however the specific dimension provided is for domestically produced firearms - the CZ have a different dimension.

CZ follow CIP (European) standards for manufacturing firearms, whereas US companies follow SAAMI/ANSI standards. There are differences between the two specifications for 22 LR barrel dimensions.

Following are the CIP minimum specifications for barrel dimensions:

22 LR - CIP
Bore: 5.38 mm (0.2118 in)
Groove: 5.58 mm (0.2197 in)

22 WMR - CIP
Bore: 5.56 mm (0.2189 in)
Groove: 5.69 mm (0.2240 in)

And for comparison, here are the SAAMI minimum specifications for barrel dimensions:

22 LR - SAAMI
Bore: 0.217 in (5.51 mm)
Groove: 0.222 in (5.64 mm)

22 WMR - SAAMI
Bore: 0.219 in (5.56 mm)
Groove: 0.224 in (5.69 mm)

As you can see, the 22 WMR dimensions are common to both CIP and SAAMI standards. However, for 22 LR, the CIP standard specifies a minimum bore dia. ~0.005 in smaller than SAAMI, and a minimum groove dia. ~0.004 in smaller.

To answer your specific question, the difference between CZ 22 WMR and CZ 22 LR groove diameters is a little over 0.004 in according to specificaiton.

None of this information is secret - this is industry standard data and is published. You may find the sources at:
http://www.cip-bobp.org
http://www.saami.org/

JMK

 

Thanks. Subsequent searching of the forum using Google rather than the inbuilt search did yield some threads with actual slugged measurements and the .22 LR RF bores do seem to vary a bit - which of-course is to be expected.

 

So what your saying is that a CZ in 22LR barrel has a tighter bore, what about 22 ammo is the bullet Diam. for American 22 ammo the same as European or different.

 

Many more accurate rifle barrels will have a slightly tighter bore or even a tapered bore. Because Anschutz barrels have bores that taper such that they get tighter toward the muzzle, it is important to never shorten an Anschutz barrel by cutting at the muzzle end. It is better to cut at the chamber end and rechamber such barrels. There is no important difference between American 22 LR ammunition and European 22 LR ammunition except the most accurate 22 LR ammunition is all made in Europe these days.

As to the actual ammunition diameters, the nominal maximum bullet diameter of 22 LR ammunition is .223". For 22 WMR and most 22 cal. small bore centerfire cartridges it is .224". * However some older (pre WW II) 218 Bee and 22 Hornet rifles have barrels with a .223" bore. If you buy one of those, It would be prudent to slug the barrel and see what you have.

How much difference this all means in the real world is called into question by my Ruger Single Six Convertable. That revolver shifts from 22 LR to 22 WMR by simply swapping cylinders. The barrel is not replaced. While I notice a drop off in BANG! when I change from 22 WMR to 22 LR, I see no difference in accuracy. In either 22LR or 22 WMR, my Single Six is the most accurate rimfire handgun I have owned.

*I find it odd that the most popular small bore centerfire round ever is called a .223 Remington, while the actual bullet diameter is .224".

 

Yes, but not just CZ barrels... 22 LR barrels made to CIP specifications.

As far as bullets:

22 LR - CIP (maximum)
Bullet: 5.72 mm (0.2252 in)

22 LR - SAAMI
Bullet: 0.2255 - 0.0040 in (5.728 - 0.102)

So, no, there really isn't any difference in bullet diameter.

JMK

 

Trying to go from memory (CRS) I seem to remember that the "Jap" 22's had a tighter bore than the American rifles--at one time Lapula used different Diameter projectiles in their Match ammo

Jim

 

The .223 Remington name is simply a marketing ploy. It follows in the footsteps of the .219 Zipper, the .220 Swift, .224 Weatherby, the .225 Winchester, et al, all of which names are simply advertising gimmicks since all use .224 diameter bullets. At one time Sierra made .223 bullets specifically for the Hornet and they may still do so. The most egregious, misleading name of all was the .22 Savage Hi-Power, or Imp, which used a .228 diameter bullet.

 

Yup, they still do, both in 40 & 45 gr: https://www.midwayusa.com/product/6...arminter-bullets-22-hornet-223-diameter-45-grain-jacketed-soft-point-box-of-100

I think Sierra is the only one. Hornady used to, but I can't find a supplier.

 

Not sure, but may be able to find out.

The only CZ in our family is a left-handed 452 American in 22LR I bought for my daughter, but a friend has the same rifle in both 22LR and 22WMR. There's an interesting story behind the 22WMR that leads me to believe there's not much difference in bore diameters. He purchased the 22WMR first and didn't know it was a magnum for a couple of months. He bought it from the local Bass Pro Shop, where it was tagged as a 22LR and shown as such on the Form 4473 when sold. He didn't read the fine print on the barrel and shot it for several months using 22LR ammo. We discovered the error when he bought a single-shot adapter for it. It wouldn't lock in the magazine well of his, so he gave it to me for my daughter to use. That struck me as odd, so we tried swapping magazines and that's when the error came to light. He went back to Bass Pro, where they told him "Oops; sorry, but you bought it and it's your problem now." He wasn't too upset because he likes the rifle, had paid the 22LR price for it, and the 22WMR was selling for good bit more at that time. He bought another in 22LR a few months later.
At any rate, the rifle had delivered very good accuracy with 22LR ammunition, which is what makes me think CZ uses a very tight bore for the 22WMR.
A gunsmith friend told me of a S&W K-22 brought to him because it was spitting a lot of lead. He said he found it was a rimfire version that had been re-chambered or fitted with a factory 22WMR cylinder and that he'd fixed it by fitting the correct 22LR cylinder. I'm a bit dubious about that because, like lots of folks here, I've got a Ruger Single Six Convertible that shoots fine with both cylinders. I also know S&W made the Mod. 53 in the .22 Remington Jet, which is a .223 (Wikipedia says the bullet diameter is .222, but my Sierra reloading book says .223.), and a lot of those came from the factory with a 22LR cylinder already fitted. And yes, Sierra does still make the .223 bullets in 40 and 45 grain versions.

 

The difference between .22LR and .22 WMR bores does not bother me that much. My Single-Six will shoot just fine with either. The one that drives me nuts is the difference between .44 Magnum pistol and .44 Magnum rifle bores. They are 0.429" and 0.431" respectively, and it's the same caliber. Explain that one for me. It's a real PITA to have to size cast bullets to two different diameters and segregate bullets and loaded ammo. So much so I am thinking about getting rid of my JM Marlin 1894.

 

Size to .430, worked great for my pistols and the 1894.

 

I've eliminated all of my leading issues with all of my .44 mags. I just shoot jacketed bullets & be happy. No more bore scrubbing, leading or aggravation.
My only cast boolits now are for my muzzle loaders !

uncle albert

ps: The proper bullet diameter for a .22 Jet IS .222. That's what the original Remington ammo had in factory loadings. Hornady still makes short runs of this bullet, but you must look for them.

 

Revolvers...

The cylinder gap in a revolver may play a part in the flexibility of those convertibles. I seem to recall something from one of Phil Sharpe's books where he was trying to get accurate readings on how much a lead bullet upsets as it goes through the gap between the cylinder and barrel. He started out by putting a short centerfire barrel, like a .32 Special, on a K-22 and firing into water or something of the sort. He found rifling marks on the slugs, so he went to a larger barrel and finally finished by taking the barrel off altogether and still thought he was seeing marks from the frame. He concluded that a soft lead slug going through that gap behaves pretty much like toothpaste coming out of the tube. That made him pay a lot more attention to the form and finishing of the forcing cone, but that's a different story.