.375 Remington Ultra Magnum

.375 Remington Ultra Magnum
Place of originUnited States
Production history
Parent case.300 Remington Ultra Magnum[1]
Case typeBeltless, rebated-rim, bottleneck
Bullet diameter.375 in (9.5 mm)
Neck diameter.4050[1]
Shoulder diameter.5250 in (13.34 mm)
Base diameter.5500 in (13.97 mm)
Rim diameter.534[1]
Case length2.850[1]
Overall length3.600 in (91.4 mm)
Rifling twist1-12"
Primer typeLarge rifle magnum
Maximum pressure65,000 psi (450 MPa)
Maximum CUP< !-- Ballistic performance --> CUP
Ballistic performance
Bullet mass/type Velocity Energy
235 gr (15 g) SP 3,148 ft/s (960 m/s) 5,172 ft⋅lbf (7,012 J)
250 gr (16 g) SBT 3,036 ft/s (925 m/s) 5,118 ft⋅lbf (6,939 J)
260 gr (17 g) Partition 2,970 ft/s (910 m/s) 5,094 ft⋅lbf (6,907 J)
270 gr (17 g) SP 2,941 ft/s (896 m/s) 5,187 ft⋅lbf (7,033 J)
300 gr (19 g) RN 2,945 ft/s (898 m/s) 5,760 ft⋅lbf (7,810 J)
Test barrel length: 26
Source(s): Alliant Powder[2]

The .375 Remington Ultra Magnum, also known as the .375 RUM is a .375 rifle cartridge introduced by Remington Arms in 2000. The cartridge is intended for large and dangerous game.[1]

It is a beltless, rebated rim cartridge created by necking up the .300 Remington Ultra Magnum case to .375 caliber with no other changes.[1] Factory loadings are less powerful than handloads for the cartridge. Remington factory loads push a 300 grain (19 g) bullet at 2760 ft/s (840 m/s),[3] producing 5070 ft·lbf (6.88 kJ) of energy. A handloader can increase the muzzle velocity of a 300gr bullet to 3321 ft/s (900 m/s),[4] and develop 5800 ft·lbf (7.9 kJ).[5]

General information[]

The intended use of this cartridge includes hunting large, thick-skinned game.[1] It is powerful enough to kill any land animal[1] and, with its high velocity, can do so at fairly long ranges. Such performance comes at the price of a heavy recoil: in a sporting-weight rifle of ~8 lb (3.6 kg), this cartridge can produce a fierce 80 ft·lbf (108 J) of recoil (approximately 3.5 times that of a .30-06.)

There is a wide selection of .375 in (9.53 mm) bullets available[1][3][6] that are suited to the high velocities of the .375 RUM, and boat tail bullets help to further extend the useful range.

Currently, there are no production rifles in this chambering (Savage & Remington previously did so.) Remington,[3] DoubleTap[7] and Nosler[6] are the only sources of factory ammunition. Loading dies and reloading data are readily available to the handloader. Double Tap loads to the specifications attributed to handloader limits.

See also[]


  1. ^ a b c d e f g h i j "375 Remington Ultra Mag" (PDF). Barnes Bullets. Barnes Bullets, LLC. 38 N Frontage Rd Mona, UT 84645. Archived from the original (PDF) on 2014-08-11. Retrieved 2014-07-26.
  2. ^ "Alliant Powder - Reloaders' Guide". Alliant Powder. Alliant Powder 2299 Snake River Avenue Lewiston, ID 83501. 2014.
  3. ^ a b c "PREMIER A-FRAME". Remington. Remington Arms Company, LLC 870 Remington Drive P.O. Box 700 Madison, NC 27025-0700. 2014. Archived from the original on 2014-07-26. Retrieved 2014-07-23.
  4. ^ "Hodgdon Online Reloading Data". Hodgdon Powder, P.O. BOX 2932 • SHAWNEE MISSION, KANSAS 66201. 2014. Archived from the original on 2007-11-11. Retrieved 2014-07-23.
  5. ^ "The .375 Remington Ultra Mag" by Chuck Hawks
  6. ^ a b "Ammunition-Nosler". Nosler. Nosler Inc. 107 SW Columbia St. Bend, OR 97702. 2014. Retrieved 2014-07-24.
  7. ^ "375 Remington Ultra Mag". DoubleTap Ammunition. DoubleTap Ammunition 646 S. Main St. #333 Cedar City, UT 84720. 2014. Retrieved 2014-07-24.

External links[]