5mm Remington Rimfire Magnum

5mm Remington Rimfire Magnum

Cartridge Data Published On: December 20, 2014 at 11:36 pm by Bullet-Blog and last updated on February 12, 2015 at 11:24 am


5mm RMR


The 5mm Remington Rimfire Magnum (AKA: 5mm RMR) is a Rimfire cartridge with a Bullet Diameter of 0.205 in” (5.21mm) that is primarily used in Rifles and Pistols. The 5mm Remington Rimfire Magnum originated in The United States in 1959. The 5mm Remington Rimfire Magnum also has a case length of 1.02 in” (25.91mm) and an overall length of 1.13 in” (28.7mm).


The 5mm Remington Rimfire Magnum, often referred to as the 5mm RMR, is a small caliber rimfire cartridge that employees a projectile ranging from 30-40 grains and is capable of velocities reaching 2500fps.

The 5mm Remington Rimfire Magnum never really caught on commercially, and was lost to obscurity in the early 1970s. Currently the only commercially loaded ammunition for the 5mm Remington Rimfire Magnum is Centurion, manufactured by Aguila.

Associated Firearms

Remington Model 591, Remington Model 592, Remington XP-100

Cartridge Details

  • Year:
  • Origin:
  • Cartridge Type:
  • Application:
  • Bullet Diameter:
  • Neck Diameter:
  • Shoulder Diameter:
  • Base Diameter:
  • Rim Diameter:
  • Rim Thickness:
  • Case Length:
  • Overall Length:
  • Primer:
  • Max Pressure:
  • CIP:
  • CIP Proof:
  • 1959
  • The United States
  • Rimmed, Bottleneck
  • Rifles
  • 0.205 in” (5.21mm)
  • 0.225 in” (5.72mm)
  • 0.259 in” (6.58mm)
  • 0.259 in” (6.58mm)
  • 0.325 in” (8.26mm)
  • 0.05 in” (1.27mm)
  • 1.02 in” (25.91mm)
  • 1.13 in” (28.7mm)
  • Rimfire (Rimfire)
  • 33000 psi (228 MPa)
  • 230 MPa (33359 psi)
  • ~299 MPa (43366 psi)

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