.50 Action Express
.50 Action Express (left) round next to a .32 ACP cartridge (right)
Place of originUnited States
Production history
DesignerEvan Whildin, Action Arms
Case typeRebated, straight
Bullet diameter.500 in (12.7 mm)
Land diameter.494 in (12.5 mm)
Neck diameter.531 in (13.5 mm)
Base diameter.543 in (13.8 mm)
Rim diameter.514 in (13.1 mm)
Rim thickness.060 in (1.5 mm)
Case length1.285 in (32.6 mm)
Overall length1.610 in (40.9 mm)
Rifling twist1:19 in
Primer typeLarge pistol
Maximum pressure36,000 psi (250 MPa)
Ballistic performance
Bullet mass/type Velocity Energy
300 gr (19 g) XTP Hornady 1,475 ft/s (450 m/s) 1,449 ft⋅lbf (1,965 J)
300 gr (19 g) GDHP Speer 1,550 ft/s (470 m/s) 1,600 ft⋅lbf (2,200 J)
325 gr (21 g) UCHP Speer 1,450 ft/s (440 m/s) 1,517 ft⋅lbf (2,057 J)
400 gr (26 g) TII WFNGC 1,200 ft/s (370 m/s) 1,279 ft⋅lbf (1,734 J)
460 gr (30 g) TII WFNGC subsonic 1,050 ft/s (320 m/s) 1,126 ft⋅lbf (1,527 J)
Test barrel length: 6 in (152 mm)
Source(s): TII Armory[1]
Accurate Powder[2]

The .50 Action Express (AE) (12.7×33mmRB) is a large-caliber handgun cartridge, best known for its usage in the Desert Eagle. Developed in 1988 by American Evan Whildin of Action Arms, the .50 AE is one of the most powerful pistol cartridges in production.[4]


The actual cartridge has a .543-inch diameter (13.8 mm) base, with a rebated rim. The rim diameter of the .50 AE is the same as the .44 Remington Magnum cartridge. A Mark XIX Desert Eagle in .50 AE can be converted to .44 with nothing more than a barrel and magazine change.[5]

The introduction of the .50 AE in the United States was met with a rocky start. Federal firearms statutes state that non-sporting firearms may not be over 0.500 inches in bore diameter (measured land to land) to meet Title I regulations. The original .50 AE bore diameter was .500 in, with conventional rifling, but the switch to polygonal rifling on production Desert Eagles allowed the gauge plug to drop through, rendering the gun a destructive device under Bureau of Alcohol, Tobacco, Firearms and Explosives (BATFE) regulations. Actual bullet diameter was reduced to the current 0.500 inches (12.7 mm) rather than the original 0.510 inches (13.0 mm)[6] – thus the noticeably tapered case.

Recoil of the .50 AE in the Desert Eagle pistol is substantial, although only marginally more severe than the .44 Magnum, as the automatic mechanism and weight of the gun smooth the recoil somewhat. Other firearms chambered for the .50 AE include the AMT AutoMag V,[7] the LAR Grizzly Win Mag, the Magnum Research BFR, and the Freedoms Arms Model 555.


SAAMI specifies a maximum chamber pressure of 36,000 pounds per square inch (250 MPa) for the .50 AE. Available factory loads can produce nearly 1,800 ft⋅lbf (2,400 J) of muzzle energy.[8]


Like other handgun cartridges of such magnitude, the principal uses of the .50 AE are metallic silhouette shooting and medium/big game hunting. Like the .44 Magnum, .454 Casull, .460 S&W Magnum, and .500 S&W Magnum, it is also well suited for defense against large predators, such as bears.[9] With heavier bullets, such as the TII Armory 400-grain and 460-grain offerings, the .50 AE closely matches the performance of the .480 Ruger and approaches the ballistics of the .500 Linebaugh.

The .50 AE as a parent case

The .50 AE is the parent case for the .440 Cor-Bon (1998) by Cor-Bon and the .429 DE (2018) by Magnum Research (a division of Kahr Firearms Group). Though similar, they are not interchangeable. Desert Eagle magazines for .50 AE cartridges can feed the derivative cartridges, but should be paired with barrels appropriate for their cartridge and caliber.[10][11]


See also


  1. ^ ".50 AE - 400 Grain WFNGC". Retrieved 2022-11-11.
  2. ^ ".50 AE loading data at Accurate Powder" (PDF). Archived from the original (PDF) on 2007-09-28. Retrieved 2007-08-12.
  3. ^ "50 American Eagles with 300-grain Gold Dot HP" (PDF). Archived from the original (PDF) on 2011-07-16. Retrieved 2009-11-11.
  4. ^ Barnes, Frank C.; Skinner, Stan (October 20, 2009). Cartridges of the World 12th Edition: A Complete and Illustrated Reference for Over 1500 Cartridges. Krause Publications. p. 568. ISBN 978-0-89689-936-0.
  5. ^ Reeves, James (2021-04-06). "Top 5 Raddest Guns from the 1980's". The Firearm Blog. Archived from the original on 2021-04-17. Retrieved 2021-04-06.
  6. ^ Taffin, John (2005),The Desert Eagle of Magnum Research.Guns Magazine
  7. ^ Fjestad, S.P. (1997). Blue Book of Gun Values (18th ed.). Minneapolis, MN: Blue Book Publications. p. 99. ISBN 1-886768-08-0.
  8. ^ "Magnum Research". 2010-12-17. Archived from the original on 2010-12-17. Retrieved 2021-04-06.
  9. ^ Ordorica, Ray (1996). Handguns /97. DBI Books. p. 179. ISBN 978-0-87349-184-6. ...in brown bear country, a 500 Linebaugh or 50 AE on the hip is a better prescription for potential maladies than anything smaller.
  10. ^ Monica Arnold (October 31, 2018). "Magnum Research Introduces New 429 DE Pistol Cartridge". Retrieved November 2, 2018.
  11. ^ "Tested: The New Magnum Research 429 DE Cartridge". American Rifleman. January 18, 2019. Retrieved January 9, 2022.