No, a 22 Magnum cannot safely shoot 22 LR ammunition under any circumstances. A firearm chambered for .22 WMR / .22 Magnum features larger chamber dimensions that do not match the smaller cartridge dimensions of standard .22 LR. Attempting to fire a .22 LR in a .22 Magnum chamber leaves the brass casing completely unsupported, causing it to rupture and vent dangerous high-pressure gas backward into the action. Ammunition compatibility requires an exact dimensional match, meaning you cannot safely mix these two rimfire rounds. The only safe exceptions are manufacturer-engineered convertible firearms utilizing separate, interchangeable cylinders for each specific caliber.
Can a 22 Magnum Shoot 22 LR?
| Feature | .22 WMR / .22 Magnum | .22 LR | Source |
| Case Length | 1.055 inches | 0.613 inches | SAAMI |
| Case Diameter | 0.242 inches | 0.226 inches | SAAMI |
| Bullet Diameter | 0.224 inches | 0.2255 to 0.226 inches | SAAMI |
| Overall Cartridge Length | 1.350 inches | 1.000 inches | SAAMI |
| Rim Diameter | 0.294 inches | 0.278 inches | SAAMI |
| Maximum Pressure | 24,000 psi | 24,000 psi | SAAMI |
| Standard Chambering | Specifically cut for .22 WMR | Specifically cut for .22 LR | SAAMI Standard |
| Can It Be Fired In A .22 WMR Chamber? | Yes (Intended) | No (Unsafe) | Firearm Manufacturers |
Standard .22 LR ammunition is absolutely not designed to be fired from a firearm chambered specifically for .22 WMR.Firing a smaller .22 LR cartridge inside a larger .22 WMR chamber results in extreme case expansion, violent brass rupture, and immediate safety hazards for the shooter. Relying on internet forums claiming that can 22 Magnum shoot 22 LR safely is dangerous and ignores strict manufacturer warnings.
Why .22 Magnum And .22 LR Are Different
The .22 Winchester Magnum Rimfire (.22 WMR) and the .22 Long Rifle (.22 LR) are distinct cartridges engineered for different performance levels. The most notable differences lie in their physical dimensions.The .22 WMR features a larger case diameter, a significantly longer case length, and a wider rim compared to the .22 LR.
The .22 LR utilizes a heeled bullet design, meaning the bullet and the outside of the brass case share a similar diameter of around 0.226 inches.In contrast, the .22 WMR uses a standard bullet seated completely inside the case mouth, requiring a larger case diameter of 0.242 inches to hold a 0.224-inch bullet.Even though both cartridges operate at the same maximum average pressure of 24,000 psi, the larger .22 WMR casing holds considerably more powder.This drives similar bullet weights at much higher velocities. Although the two rounds share the “22” naming convention, ammunition that looks similar is not necessarily interchangeable.
.22 WMR vs .22 LR Dimensions
| Dimension | .22 WMR | .22 LR | Source |
| Case Length | 1.055 inches | 0.613 inches | SAAMI |
| Rim Diameter | 0.294 inches | 0.278 inches | SAAMI |
| Case Diameter | 0.242 inches | 0.226 inches | SAAMI |
| Bullet Diameter | 0.224 inches | 0.2255 inches | SAAMI |
| Overall Length | 1.350 inches | 1.000 inches | SAAMI |
| Maximum Pressure | 24,000 psi | 24,000 psi | SAAMI |
.22 Magnum Chamber vs .22 LR Chamber
Firearm chambering is the controlling factor for 22 Magnum ammunition compatibility because the chamber acts as a precision mold that supports the brass casing during ignition. A 22 Magnum chamber is cut wider and longer than a 22 LR chamber to perfectly accommodate the larger magnum cartridge.
If a .22 LR cartridge is placed inside a .22 WMR chamber, it will fit very loosely due to its narrower diameter. The case will lack crucial support along its walls. Because rimfire cartridges headspace on the rim, the .22 LR cartridge might sit slightly off-center since its smaller 0.278-inch rim diameter rests loosely inside the larger 0.294-inch rim cut of the .22 Magnum chamber. Upon firing, the thin brass of the .22 LR expands violently to fill the wider chamber space, leading to severe case ruptures, extraction failures, and trapped brass.
Can You Put .22 LR In A .22 Magnum Rifle?
No, you cannot safely put .22 LR ammunition into a standard .22 Magnum rifle. The general manufacturer and standards-based position is that you must only use the specific ammunition stamped on the firearm’s barrel. Standard .22 LR is not approved for use in firearms chambered for .22 WMR. If you are wondering can a 22 WMR shoot 22 LR, attempting to fire smaller ammunition in a larger chamber violates essential firearm safety rules and will result in case failure, erratic performance, and potential injury from escaping hot gases.
Can You Shoot .22 WMR In A .22 LR Rifle?
No, you absolutely cannot shoot .22 WMR in a .22 LR rifle. This is physically impossible under normal circumstances, and attempting to force it is a severe safety issue. The .22 WMR cartridge has a case length of 1.055 inches, which is nearly half an inch longer than the .22 LR case.Furthermore, the wider case diameter of the .22 WMR will prevent the round from seating into a .22 LR chamber. Ammunition must match the firearm’s chambering exactly unless the firearm manufacturer specifically provides another approved configuration.
Exceptions And Convertible Firearms
The only safe way to shoot both .22 LR and .22 WMR from the same firearm is by using a platform explicitly designed for dual compatibility through interchangeable parts. Certain single-action revolvers are manufactured as convertible configurations.
Models such as the Ruger Single-Six, the Ruger Super Wrangler, and the Heritage Rough Rider ship from the factory with two completely separate cylinders. One cylinder is chambered exclusively for .22 LR, and the other is chambered exclusively for .22 WMR. To switch ammunition, the user must physically remove the cylinder from the frame and install the corresponding manufacturer-approved cylinder. You cannot fire .22 LR safely out of the .22 WMR cylinder even in a convertible revolver, nor are 22 LR and 22 WMR interchangeable in the same cylinder.
.22 Magnum vs .22 LR Ballistics
The dimensional differences between the two cartridges result in vastly different ballistics.Typical .22 LR ballistics feature a 36 to 40-grain bullet traveling between 1,050 and 1,250 feet per second, yielding around 130 to 140 foot-pounds of muzzle energy.Its practical range is typically limited to about 50 to 100 yards.
The .22 WMR typically fires a 30 to 40-grain bullet at velocities ranging from 1,800 to 2,200 feet per second, generating well over 300 foot-pounds of muzzle energy.This flatter trajectory extends the practical range to 100 or 150 yards for small game hunting. While the 22 WMR vs 22 LR ballistics are very different, shooters must never confuse ballistic performance with ammunition compatibility.
Why Ammunition Compatibility Matters
Using the wrong cartridge can create incredibly dangerous conditions for the shooter and bystanders. Incorrect chamber fit results in poor cartridge support, meaning the thin brass casing must contain the pressure of the explosion entirely on its own.It will fail.
Improper headspacing can also cause the firing pin to strike the rim out of alignment, leading to a failure to fire. If the round does ignite, the unsupported case splits, and the 24,000 psi of pressure must escape.This pressure blows backward into the action, which can launch unburned powder, brass fragments, and hot gas directly into the shooter’s face. Additionally, case ruptures lead to stuck casings that require tools to extract, potentially scoring the chamber or breaking the firearm’s extractor mechanism.
Manufacturer Guidance
Leading firearm and ammunition manufacturers stringently advise against mixing rimfire ammunition. The Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) publishes technical specifications that dictate firearms should only be paired with their exact matching ammunition designations. Firearm manufacturers like Ruger explicitly note in their manuals that convertible cylinders are specific to their respective calibers, and even warn that cylinders are not universally interchangeable between different revolver models.
Pros And Cons
Using .22 LR In A Firearm Specifically Designed For .22 LR
The primary benefit of using .22 LR ammunition in its intended chamber is safety and flawless reliability. The ammunition is highly affordable, features virtually no recoil, and is very quiet.The tight chamber fit ensures excellent accuracy and smooth extraction.The limitation is its lower kinetic energy and shorter effective range compared to magnum cartridges.
Using .22 WMR In A Firearm Specifically Designed For .22 WMR
Using .22 WMR in a dedicated .22 Magnum chamber safely unlocks significantly higher velocity and kinetic energy.It offers a much flatter trajectory, making it highly effective for pest control and small game at longer distances. The limitations include higher ammunition costs, louder reports, and increased muzzle blast compared to standard rimfire rounds.
FAQs
Can a 22 Magnum shoot 22 LR?
No, a firearm chambered for 22 Magnum cannot safely shoot 22 LR because the chamber is too wide and long, which causes the smaller 22 LR casing to rupture upon firing.
Can you shoot 22 LR in a 22 Magnum rifle?
No, you cannot. Firing 22 LR in a 22 Magnum rifle creates a severe safety hazard, as the brass casing will split and release high-pressure gases back into the action.
Can you shoot 22 Magnum in a 22 LR rifle?
No, it is physically impossible to chamber a 22 Magnum cartridge in a 22 LR rifle because the 22 Magnum casing is much longer and wider than the 22 LR chamber.
Is 22 Magnum the same size as 22 LR?
No, the 22 Magnum is noticeably larger in every dimension, featuring a longer case, wider body, and a larger rim diameter than the 22 LR.
What is the difference between 22 WMR and 22 LR?
The primary difference is the size of the cartridge case. The 22 WMR uses a larger casing that holds more gunpowder, producing higher velocities and greater energy than the 22 LR.
Are 22 Magnum and 22 LR interchangeable?
No, these cartridges are never interchangeable. A shooter must only use the specific ammunition caliber stamped on the barrel of the firearm.
Can a convertible revolver shoot both 22 LR and 22 Magnum?
Yes, but only if the shooter manually swaps the cylinder. Convertible revolvers come with two distinct cylinders, one specifically machined for 22 LR and one specifically machined for 22 Magnum.
Why can’t a 22 LR firearm use 22 Magnum ammunition?
A 22 LR firearm cannot use 22 Magnum ammunition because the chamber is physically too short and too narrow to accept the larger magnum cartridge.
Does 22 Magnum use the same bullet diameter as 22 LR?
They are very close but not exactly the same. The 22 Magnum generally uses a 0.224-inch bullet, while the 22 LR uses a slightly wider 0.2255-inch heeled bullet.
What happens if the wrong 22 cartridge is used?
Using the wrong cartridge causes improper headspacing, failure to fire, split brass casings, stuck cases, and potential injury to the shooter from escaping high-pressure gas.