Why no 22LR Rimless?

[Skans]

Why hasn't anyone developed a 22 long rifle (or magnum) rimless cartridge - one that still doesn't use a primer insert? Seems like it would be possible. The advantage would be higher capacity magazines and more reliable feeding in semi-autos.

[Microgunner]

The rim is necessary for a rimfire cartridge.
A rimless 22lr would need to be centerfire.

[kraigwy]

Kind of hard to have a Rim Fire without a Rim

But the closest I've see is the Pin Fire Ammo.

[carguychris]

The rim is necessary for a rimfire cartridge.

+1; the rim allows the firing pin to crush the primer against a solid backing surface- the edge of the chamber.

The main design problem with a "rimless rimfire" cartridge would be ensuring reliable ignition without piercing the case or weakening it so much that it comes apart during extraction. The design would have to incorporate some sort of device to support the "rim" as the firing pin strikes it, yet doesn't interfere with extraction.

[Nickel Plated]

The design would have to incorporate some sort of device to support the "rim" as the firing pin strikes it, yet doesn't interfere with extraction.

The extractor?

The extractor claw grabs the rim from the front like it usually does. And the firing pin strikes it from the back, crushing the rim between the firing pin and extractor.

Though the biggest upside of 22LR is the cheap ammo. With the cost of buying a new rifle and some newly designed niche ammo, you may as well just get some common, low-caliber centerfire.

[jmr40]

Rimfire ammo is much cheaper to manufacture. A rimless centerfire 22 with about the same power as standard 22 LR ammo would certainly be possible. But the cost would be about the same as 223 ammo.

Instead of paying $15-$20 for 500 rounds you will be paying $8-$10 for 20 rounds. Possibly more. I don't see much of a market.

[Jo6pak]

I also agree it's a cost/benefit issue. Along with the old "if it ain't broke.." arguement.

In the past, there have been a few centerfire 22 cartridges (22WCF and 22 Maynard come to mind) but none have been able to compete with the rimfires

[Old Grump]

The 22 LR round has a heeled bullet, the front half of the bullet is the same diameter as the case and there would be nothing for the case to head space on. You need the rim.

Imagine the manufacturers dilemma, do they make the case diameter larger making all the chambers of all 22 rifles and pistols useless or reduce the size of the bullet making all the barrels chambered for the 22 useless. There there is the matter of rebating the case to allow an extractor to grab the 22 case for removal and it just gets more fun from there. Sometimes it is better to let a proven product that is still doing the job for which it was designed and does it very well to just be. I'd be ticked if I couldn't find ammo for my 22's anymore and even more ticked if I had to re-chamber or re-barrel 12 of my guns in order to shoot a new round which would undoubtedly be much more expensive and not any better than what we have.

[Ideal Tool]

Hello, everyone..interesting posts! I kind of chuckled when I first read about a rimless rimfire..But then I got to thinking...what if we could start with a clean sheet of drafting paper..and design a true rimless "rimfire"?
First thing would be to make it inside lubed..this would accomplish two things..get rid of that pesky "heel" that has been a stumbling block to accuracy from day 1, & provide a flat square case mouth to headspace on.
Now..as to ignition...when Remington first came out with their electronic primers..the ETRONx..I kind of figured it would flop...However, at the time, I remember thinking..if their ever was a ctg. that would benifit from electric ignition..it would be the .22 rimfire. The priming is the most critical element to accuracy & reliability in a rimfire..with electronic ignition..no more concern about uniformity of brass hardness in rim area, or uniformity of compound spun in rim cavity. The pin wouldn't even need to dent the case...merely make firm contact.
Can we look forward to such a ctg.? probably not..but Skans idea has merit.

[Jo6pak]

Interesting spin on the concept Ideal. That's thinking outside the box..or is it outside the rim??

[ballardw]

I think the old Velo Dog, http://www.ammo-one.com/5-75VeloDog.html comes close but it was still rimmed. But it looks like it might be possible to turn the rim down to semi-rimmed.

Fiocchi is apparently supposed to be making some of this ammo.

[Sport45]

The rimfire brass is like a miniture of the old balloon head revolver cases. If you made it rimless you would loose a significant amount of case capacity. To compensate for that, you'd have to make it longer. That would make it hard to fit in handgun grips and reduce the amount you could put in a tubular magazine. Actions would have to be made longer as well.

[22-rimfire]

Why would you bother when you have the 25 ACP?

[Skans]

My thinking behind a .22LR (or similar) rimless case is this: The cartridges would stack up easier and more uniform in a magazine - huge increase in capacity, with minimal increase in magazine or firearm design. Also, there should be a corresponding increase in reliable feeding.

Or, what if you increased the overall width of the cartridge so that the rim of the .22 is no longer protruding, yet keeping it technically rimfire.

[RedBowTies88]

I don't think capicity with the rim is a problem, I mean if kel-tec can fit 30 .22 mags in a pistol 30 LR's could sure be done.

Just seems like no one wants to be bothered with designing one.