The .22 Hornet is a historic, low-capacity rimmed centerfire rifle cartridge governed by precise SAAMI and C.I.P. standards.Its primary structural measurements include a standardized bullet diameter of 0.224 inches (5.7 mm), a maximum case length of 1.403 inches (35.6 mm), and a maximum overall cartridge length (COAL) of 1.723 inches (43.8 mm). The rimmed case features a rim diameter of 0.350 inches (8.9 mm) and a base diameter just forward of the rim measuring 0.298 inches (7.6 mm), tapering down to a shoulder diameter of 0.276 inches (7.0 mm) and a neck diameter of 0.243 inches (6.2 mm). Depending on whether data is sourced from U.S. SAAMI specifications or European C.I.P. tables, published figures can reflect nominal design baselines, maximum chamber limits, or historical pressure variations.
22 Hornet Dimensions
| Dimension | Inches | Millimeters | Specification Type | Source | Notes |
| Bullet Diameter | 0.224 in | 5.7 mm | Nominal / Standard | SAAMI / C.I.P. | Standard .224 caliber modern projectile diameter |
| Case Length | 1.403 in | 35.6 mm | Maximum | SAAMI / C.I.P. | Maximum length from case mouth to base |
| Overall Cartridge Length (COAL) | 1.723 in | 43.8 mm | Maximum | SAAMI / C.I.P. | Maximum length to fit standard mini-action magazines |
| Rim Diameter | 0.350 in | 8.9 mm | Maximum | SAAMI / C.I.P. | Distinct rimmed profile providing headspace support |
| Base Diameter | 0.298 in | 7.6 mm | Maximum | SAAMI / C.I.P. | Case body diameter just forward of the extraction groove |
| Shoulder Diameter | 0.276 in | 7.0 mm | Maximum | SAAMI / C.I.P. | Measured at the body-to-shoulder junction |
| Neck Diameter | 0.243 in | 6.2 mm | Maximum | SAAMI / C.I.P. | Outer diameter of the charged or chamber neck |
| Shoulder Angle | 35° | 35° | Nominal Design | C.I.P. | Traditional sloped shoulder geometry |
| Case Capacity | ~14.0 gr H₂O | ~0.91 ml | Nominal / Usable | Measured / Typical | Internal water capacity to the case mouth |
| Maximum Pressure | 25,000 psi (SAAMI) / 43,000 psi (C.I.P.) | 172 MPa / 300 MPa | Maximum Average Pressure | SAAMI / C.I.P. | Varies by region and vintage firearm safety ceilings |
Understanding The 22 Hornet Dimensions
Analyzing the specific 22 Hornet cartridge dimensions reveals how each geometric measurement contributes to its performance as a low-recoil, efficient small-game and varmint round.
- Bullet Diameter: Standardized at 0.224 inches, this diameter matches modern rifle bore groove dimensions, though vintage legacy rifles occasionally featured tighter .223-inch bores.
- Case Length:The 1.403-inch maximum case length provides a compact profile that houses minimal powder while generating high velocities for its size.
- Rim and Base Diameters: Featuring a rim diameter of 0.350 inches and a base of 0.298 inches, the cartridge headspaces on its rim, eliminating the need for complex belt or shoulder precision in older break-action platforms.
- Shoulder Geometry: The 0.276-inch shoulder diameter transitions with a mild slope, optimizing internal volume and facilitating smooth feeding.
- Neck Dimensions & Length: The 0.243-inch neck diameter securely grips light projectiles, ensuring appropriate neck tension.
- Overall Cartridge Length (COAL):Bounded at a maximum of 1.723 inches, ensuring safe function in compact bolt-action and single-shot rifles.
- Case Capacity:Holding roughly 14 grains of water depending on brass brand, its compact volume demands fast-burning propellants.
22 Hornet Dimensions In Inches And Millimeters
| Measurement Category | Dimension (Inches) | Dimension (Millimeters) |
| Bullet Diameter | 0.224 in | 5.7 mm |
| Case Length (Max) | 1.403 in | 35.6 mm |
| Overall Cartridge Length (Max) | 1.723 in | 43.8 mm |
| Base Diameter | 0.298 in | 7.6 mm |
| Rim Diameter | 0.350 in | 8.9 mm |
| Shoulder Diameter | 0.276 in | 7.0 mm |
| Neck Diameter | 0.243 in | 6.2 mm |
22 Hornet Case Dimensions
The 22 Hornet case dimensions define a classic, small-capacity bottlenecked profile. The brass case measures a maximum length of 1.403 inches, stepping down gradually from a base diameter of 0.298 inches to a shoulder diameter of 0.276 inches.
Because the case walls are exceptionally thin compared to larger centerfire rifle brass, handloaders must exercise caution during resizing. Nominal case dimensions adhere strictly to SAAMI and C.I.P. tolerances, ensuring that commercial ammunition chambers reliably across a wide array of historic and contemporary firearms.
22 Hornet Bullet Diameter
The standardized 22 Hornet bullet diameter is 0.224 inches (5.7 mm). It is vital to distinguish this standard projectile diameter from bore and groove measurements. While modern barrels feature a 0.224-inch groove diameter, many vintage rifles manufactured prior to World War II utilized a 0.223-inch groove dimension.
Firing modern 0.224-inch bullets through tight vintage .223 bores can result in elevated chamber pressures. Commonly loaded projectile weights span from 30 to 45 grains, all maintaining this uniform outer diameter.
22 Hornet Overall Cartridge Length
The published maximum overall length for the 22 Hornet is 1.723 inches (43.8 mm). This dimension is critical for ensuring that loaded rounds fit inside the internal box magazines of compact repeating rifles.
Actual loaded cartridge lengths often vary slightly depending on whether a builder uses blunt soft-point bullets or longer polymer-tipped projectiles. Keeping the total length at or below 1.723 inches prevents binding during the feeding cycle.
22 Hornet Case Capacity
The 22 Hornet case capacity averages approximately 14.0 grains of water, though internal volume varies noticeably among commercial brass manufacturers (such as Winchester, Remington, PPU, and Hornady).
Because the case holds such a small volume of powder (typically 10 to 13 grains), even minor variations in internal capacity significantly impact internal ballistics and chamber pressure. Handloaders must treat different brass brands as distinct entities and avoid interchanging loads without working up safely.
22 Hornet Dimensions vs Similar Cartridges
Comparing the 22 Hornet with other small-caliber centerfire and rimfire rounds highlights its unique transitional position in ballistics.
| Cartridge | Bullet Diameter | Case Length | Overall Length | Rim / Base Diameter | Case Capacity | Source |
| 22 Hornet | 0.224 in | 1.403 in | 1.723 in | 0.350 / 0.298 in | ~14.0 gr H₂O | SAAMI / C.I.P. |
| .17 Hornet | 0.172 in | 1.350 in | 1.720 in | 0.350 / 0.299 in | ~11.0 gr H₂O | SAAMI |
| .222 Remington | 0.224 in | 1.700 in | 2.130 in | 0.378 / 0.365 in | ~28.0 gr H₂O | SAAMI |
| .223 Remington | 0.224 in | 1.440 in* | 2.260 in | 0.378 / 0.376 in | ~30.0 gr H₂O | SAAMI |
| .22 WMR | 0.204 in | 1.055 in | 1.350 in | 0.376 / 0.242 in | Rimfire | SAAMI |
(Note: .223 Remington case length is 1.760 inches).
22 Hornet vs .223 Remington Dimensions
Comparing the 22 Hornet to the ubiquitous .223 Remington demonstrates a massive scale difference. The .223 Remington features a much larger case length (1.760 in vs. 1.403 in) and a substantially greater base diameter (0.376 in vs. 0.298 in), resulting in more than double the powder capacity (~30 gr vs. ~14 gr).
While both fire the same 0.224-inch bullet diameter, the .223 Remington operates at much higher pressures (55,000 psi) and requires standard-length actions, whereas the Hornet operates at lower pressure ceilings and thrives in lightweight mini-actions.
22 Hornet vs .17 Hornet Dimensions
The modern .17 Hornet is directly derived from necking down the 22 Hornet case. While they share an identical rim diameter (0.350 inches) and nearly matching overall lengths (~1.72 inches), the .17 Hornet steps the bullet diameter down to 0.172 inches and pushes the shoulder forward slightly, resulting in a slightly modified case volume. Both cartridges cater to similar low-noise, short-range varmint hunting roles.
22 Hornet Chamber And Cartridge Dimensions
Chamber specifications for the 22 Hornet are engineered around rim headspacing. The chamber dimensions match the cartridge rim thickness (approximately 0.065 inches) to ensure the bolt face locks securely against the rear of the case.
Because operating pressures are relatively modest, chamber wear is minimal compared to ultra-high-velocity magnums, though proper reamer tolerances remain vital for ensuring smooth extraction of rimmed brass.
22 Hornet Bullet Weight And Dimensions
Factory ammunition and handloads for the 22 Hornet typically utilize lightweight bullets ranging from 30 grains to 46 grains, with 35-grain polymer-tipped and 45-grain soft-point options being the most common.
While projectile weight does not alter standard case dimensions, longer or uniquely profiled bullets must be seated carefully to ensure the loaded round stays within the 1.723-inch overall length limit required for magazine compatibility.
Why 22 Hornet Dimensions Matter
Paying close attention to 22 Hornet cartridge dimensions is essential for several practical reasons:
- Chamber Safety: Ensures proper matching of bullet diameter to prevent excessive pressures in legacy .223-bore barrels.
- Headspacing: Guarantees correct rim contact and reliable lockup in break-action or bolt-action rifles.
- Magazine Feeding: Confirms that loaded rounds comply with overall length limits for smooth cycling.
- Reloading Precision:Accounts for thin brass walls and small case volume during powder charging.
Manufacturer Specifications vs Independent Measurements
Official dimensions for the 22 Hornet are standardized globally by SAAMI in the United States and C.I.P. in Europe.
While commercial manufacturers closely follow these blueprints, independent measurements of surplus or foreign-made brass can reveal slight variations in wall thickness and internal volume. Official standards remain the definitive benchmark for reamer design, manufacturing, and safety evaluation.
Common Questions
What are the dimensions of 22 Hornet?
The 22 Hornet features a bullet diameter of 0.224 in, a case length of 1.403 in, a maximum overall length of 1.723 in, a base diameter of 0.298 in, and a rim diameter of 0.350 in.
What is the 22 Hornet case length?
The maximum case length is 1.403 inches (35.6 mm).
What is the 22 Hornet overall length?
The maximum overall cartridge length (COAL) is 1.723 inches (43.8 mm).
What is the 22 Hornet bullet diameter?
The standardized bullet diameter is 0.224 inches (5.7 mm).
What is the 22 Hornet rim diameter?
The rim diameter is 0.350 inches (8.9 mm).
What is the 22 Hornet base diameter?
The base diameter is 0.298 inches (7.6 mm).
What is the 22 Hornet case capacity?
The nominal case capacity is approximately 14.0 grains of water.
How does 22 Hornet compare with .223 Remington dimensions?
The .223 Remington is significantly larger, featuring a 1.760-inch case length and double the powder capacity (~30 gr vs. ~14 gr), though both share a 0.224-inch bullet diameter.
What is the maximum pressure for 22 Hornet?
SAAMI maximum average pressure is 25,000 psi, while C.I.P. piezo standards rate it up to 43,000 psi.
Final Verdict
The 22 Hornet is defined by its 0.224-inch bullet diameter, 1.403-inch case length, and 1.723-inch maximum overall length, establishing a compact, highly efficient rimmed cartridge profile.Its 0.350-inch rim diameter and modest ~14-grain case capacity allow it to deliver low-recoil performance ideal for light varmint work. Understanding its precise dimensional specifications, historical bore variations, and pressure standards is essential for safe handling and accurate shooting.