Practice & target
Full-metal-jacket, plated, lead, and wadcutter bullets describe different constructions. Grain weight is projectile mass; it does not state a powder charge or guarantee recoil.
THE CARTRIDGE LIBRARY · PISTOL
.50 Action Express
A large semiautomatic-pistol cartridge often abbreviated .50 AE. Its rebated-rim design and .50-caliber bullet belong to a different cartridge family from .500 S&W Magnum.
2A Ledger reference desk · Sources checked October 18, 2026
Read the dimensions
- Overall · min–max
- 1.555–1.595 in
39.497–40.513 mm - Case length · max
- 1.285 in
32.639 mm - Bullet maximum
- 0.502 in
12.751 mm - Rim diameter · max
- 0.515 in
13.081 mm
Know the exact name
At a glance
- Cartridge family
- Pistol
- Bullet specification
- 0.5020 in / 12.751 mmBullet maximum
- Factory examples
- 2 loadsSelected, sourced examples below
- Weight in cited examples
- 300 grGrains measure mass, not powder charge
.50 Action Express is identified by its complete cartridge designation. The resource-table alternative is 50 AE. A caliber number, bullet diameter, or family resemblance on its own does not identify ammunition compatibility.
.50 AE, .50 Beowulf, .50 BMG, and .500 S&W Magnum are separate specifications.
Dimensions: open the exact dimensional drawing ↗. The displayed number is bullet maximum, rather than an assertion that every manufactured projectile or barrel has this exact diameter.
Origins & evolution
Background & development
The .50 Action Express originated in the late 1980s and became a commercial ammunition offering through CCI-Speer in 1991. Its development was closely associated with the Desert Eagle, a gas-operated self-loading pistol large enough to accommodate a cartridge well outside the dimensions of ordinary service-pistol ammunition.
A rebated rim let the broad cartridge body use a smaller case-head envelope, an important part of fitting it into that firearm system. Early experimental bullet dimensions also differed from the eventual .500-inch production form, so the final standardized cartridge should not be confused with every prototype described in its development history. The .50 AE became the best-known chambering associated with the Desert Eagle’s public image, although that pistol family also used other cartridges. Its historical significance lies in bringing a very large-bore sporting cartridge to a production self-loading handgun, rather than following the more usual large-revolver route.
Historical sources: Magnum Research archive: original Desert Eagle test and .50 AE development account ↗
Construction changes the story
Loads, variations & specialty offerings
Expanding factory bullets
JHP, XTP, FTX, HST, and similar product names refer to particular designs. Muzzle energy alone does not show expansion, penetration, or reliability in a particular firearm.
Specialty load families
Reduced-recoil, subsonic, monolithic, and heavier-bullet offerings are product-specific. A +P marking is a pressure category where standardized, not simply a heavier bullet. Follow the maker’s exact product and firearm guidance.
In the cited .50 Action Express examples, bullet weights are 300 grains. These are the weights actually present in this source selection, not a claim that every possible loading is listed.
Bullet construction background: Hornady: anatomy of a bullet ↗. Exact product descriptions and velocities are cited in the factory table.
From the factory catalog
300 grains
1,550 fps
FUSION SP
Compare all 2 cited factory load records
| Maker / product | Bullet mass | Published construction | Muzzle velocity | Test barrel | Source |
|---|---|---|---|---|---|
| FederalF50AEFS1 | 300 gr 19.44 g | FUSION SP | 1,550 fps 472 m/s | Not stated here; see source | Federal · PDF p. 61 ↗ |
| Hornady9245 | 300 gr 19.44 g | XTP® | 1,475 fps 450 m/s | 6 in | Hornady · PDF p. 191 ↗ |
Explore the published data
Ballistics you can inspect
Select a legend entry to add or remove its line. Hover or tap a plotted point, or use the position slider. With the graph focused, arrow keys move the inspector. Solid dots identify source points; dashed connectors show estimates between them. Load construction, pressure category, and test setup can differ even at the same grain weight.
Read the original values as accessible tables
.50 Action Express: factory velocity downrange
| Exact load | Source | Published points |
|---|---|---|
| 300 gr Federal FUSION SP | Federal | 0: 1550; 25: 1451; 50: 1361; 75: 1278; 100: 1205 |
| 300 gr Hornady XTP® | Hornady | 0: 1475; 50: 1251; 100: 1092 |
How to interpret the comparison
Changing bullet weight also often changes bullet design and propellant choice. Two curves are comparisons of the listed products, not a controlled experiment proving that bullet weight alone caused the difference. Catalog downrange points are projections under the maker’s conditions; barrel-study points are recorded observations in the study firearm.
Direct answers
Common questions
What is .50 Action Express?
A large semiautomatic-pistol cartridge often abbreviated .50 AE. Its rebated-rim design and .50-caliber bullet belong to a different cartridge family from .500 S&W Magnum.
What diameter does .50 Action Express use?
The cited dimensional standard lists 0.5020 inches (12.751 mm), bullet maximum. This drawing convention is different from a casual caliber nickname.
Are similarly named cartridges interchangeable?
.50 AE, .50 Beowulf, .50 BMG, and .500 S&W Magnum are separate specifications.
Are the graph values measured or estimated?
The downrange view uses the exact manufacturer catalog records shown in the source table. Dashed connectors and intermediate inspector values use linear interpolation between the displayed source points. Calculated energy uses the listed bullet mass and velocity.
Does higher energy mean the best load?
Energy is calculated from mass and velocity. It does not establish accuracy, expansion, penetration, pattern density, recoil, or suitability for a particular firearm. Use the exact product documentation and firearm manual.
Trace the facts
Sources & methodology
Skives & petals: read the jacket construction →
Compiled by 2A Ledger from the linked standards, manufacturer publications, and identified test records. Checked October 18, 2026. Historical tests and older catalogs retain their original dates; a listing here does not establish current availability.
- SAAMI: dimensional drawing · PDF p. 66 ↗
- Federal · PDF p. 61 ↗
- Hornady · PDF p. 191 ↗
- Magnum Research archive: original Desert Eagle test and .50 AE development account ↗
Diameter figures preserve the cited drawing convention. Inch–millimeter conversion uses exactly 25.4 mm per inch. Factory specifications describe the maker’s test setup; your firearm, ammunition lot, temperature, and measuring method can produce different results. This is an educational factory-ammunition reference, not a reloading manual.