The .375 Whelen cartridge

Cartridge (firearms)

A cartridge, also called a round, packages the bullet, gunpowder and primer into a single metallic case precisely made to fit the firing chamber of a firearm. The primer is a small charge of impact-sensitive chemical that may be located at the center of the case head or at its rim . Electrically...

 (A.K.A. 375-06) was developed in 1951 by L.R. "Bob" Wallack and named in honor of Colonel Townsend Whelen. It is a .30-06 Springfield

.30-06 Springfield

The .30-06 Springfield cartridge or 7.62×63mm in metric notation, was introduced to the United States Army in 1906 and standardized, and was in use until the 1960s and early 1970s. It replaced the .30-03, 6 mm Lee Navy, and .30 US Army...

 case necked up to .375. While the .375 Whelen retains the .30-06's shoulder angle of 17° 30′, an improved version was introduced with a 40°  angle, providing more case capacity as well as better headspacing. The .375 Whelen Improved is favored by most.

Reloading Data

Bullet (grs.)	Powder / (grs.)	MV	ME
200 SP	IMR4064 / 58.0	2450	2265
235 SP	IMR4064 / 60.0	2475	3205
270 SP	IMR4064 / 57.0	2380	3400
300 SP	IMR4064 / 52.0	2110	2975

See also

• List of rifle cartridges
• .30-06 descendants
  .30-06 Springfield Wildcat Cartridges
  Wildcat cartridges are firearms cartridges whose dimensions have been modified. Usually these modifications are with an eye toward improved performance, either measurable or not. This article deals with wildcat cartridges which result from a simple necking down or up of the original .30-06...