.375 Winchester

The .375 Winchester is a modernized version of the .38-55 Winchester, a black powder cartridge from 1884. It was introduced in 1978 along with the Winchester Model 94 “Big Bore” lever action rifle, which was in production from 1978 until 1986.[3]

.375 Winchester
Foreground: .375 Winchester. Left to right: 8mm Mauser, .308 Winchester, .375 Winchester, .22 Long Rifle.
Type	Rifle
Place of origin	United States
Production history
Designed	1978
Manufacturer	Winchester
Produced	1978–present
Specifications
Parent case	.38-55 Winchester
Case type	Rimmed, straight
Bullet diameter	.375 in (9.5 mm)
Land diameter	.366 in (9.3 mm)[1]
Neck diameter	.400 in (10.2 mm)
Base diameter	.420 in (10.7 mm)
Rim diameter	.506 in (12.9 mm)
Rim thickness	.063 in (1.6 mm)
Case length	2.020 in (51.3 mm)
Overall length	2.560 in (65.0 mm)
Maximum pressure (CIP)	55,000 psi (380 MPa)
Maximum CUP	52,000[2] CUP
Ballistic performance
Bullet mass/type Velocity Energy 200 gr (13 g) JFP 2,223 ft/s (678 m/s) 2,194.12 ft⋅lbf (2,974.83 J) 200 gr (13 g) JFP 2,419 ft/s (737 m/s) 2,598.09 ft⋅lbf (3,522.54 J) 220 gr (14 g) JFP 2,029 ft/s (618 m/s) 2,010.66 ft⋅lbf (2,726.09 J) 220 gr (14 g) JFP 2,236 ft/s (682 m/s) 2,441.85 ft⋅lbf (3,310.70 J)
Source(s): Hodgdon Online Reloading Data

Though very similar in appearance to the .38-55 Winchester parent cartridge, the .375 Winchester cartridge has a shorter case length and operates at a higher chamber pressure of 52,000 CUP or 55,000 psi (380 MPa), compared to the .38-55 Winchester cartridge which has a longer case length and operates at a lower chamber pressure of 30,000 CUP or 35,000 psi (240 MPa).

The most commonly used bullet weights for the .375 Winchester are between 180 gr to 260 gr (11.7 g to 16.9 g) and has been used on a variety of medium to large game species such as whitetail, pronghorn, caribou, elk, moose, black bear, and brown bear.[4]