The .500 Whisper or .500 Whisper Short Belted is a subsonic rifle cartridge developed by

SSK Industries SSK Industries, Inc. is an American designer and manufacturer of firearms and accessories in Wintersville, Ohio. Founded in 1977, the company is known for its custom Contender and Encore barrels. Started by hunter and gun enthusiast J. D. Jones ...

for use in suppressed rifles. It is capable of firing a .51 caliber bullet weighing at roughly .

Overview

The .500 Whisper (metric: 13×57mmB
by Anthony G Williams, ''CARTRIDGES FOR SILENCED SNIPING RIFLES'', January 2013) is the first of two rounds developed by

J. D. Jones J. D. Jones (born November 21, 1936) is an American firearms and cartridge designer, firearms writer and founder of SSK Industries. Jones began hunting at an early age, and became interested in bullet casting and handloading firearms cartridge ...

with a specific focus on the Thumper concept and subsonic use. Being based on the .378 Weatherby Magnum case, it is a belted and bottlenecked cartridge. Later,

went on to develop the similar .510 Whisper round. This has a roughly shorter non-belted bottlenecked case based on the .416 Rigby. Despite the large bullet, this round is very quiet when using a

suppressor A silencer, also known as a sound suppressor, suppressor, or sound moderator, is a gun barrel#Muzzle, muzzle device that suppresses the muzzle blast, blast created when a gun (firearm or airgun) is discharged, thereby reducing the sound inten ...

due to the subsonic nature of the cartridge. When used with a very high ballistic coefficient bullet, the round only loses about out to over . This gives it more downrange energy at that distance than traditional .30 caliber rounds such as the .308 Winchester and .300 Winchester Magnum.Whisper cartridges
" by Lukas Kruesi, ''New Zealand Guns & Hunting'', September/October 2003 Sako TRG-S test rifles have achieved

minute of angle A minute of arc, arcminute (abbreviated as arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of a degree. Since one degree is of a turn, or complete rotation, one arcminute is of a tu ...

, and better, accuracy with this cartridge at . Powders such as H110, 4227, or surplus WC820 are well suited for subsonic loads and give a low

standard deviation In statistics, the standard deviation is a measure of the amount of variation of the values of a variable about its Expected value, mean. A low standard Deviation (statistics), deviation indicates that the values tend to be close to the mean ( ...

. Necessary components such as barrels, reloading dies, etc. are available from SSK.

Sako Sako Limited (natively ) is a Finnish firearm and ammunition manufacturer located in Riihimäki, Tavastia Proper in southern Finland. It also has owned the Tikka brand of bolt-action rifles since 1983, and is now owned by the Italian firear ...

TRG-S actions are most often converted to this caliber. The Thompson Center Encore is also suitable, but is rather lightweight for shooting this heavy recoiling cartridge, especially when using bullets.

Design

The case of the .500 Whisper is derived from the big-bore belted family of cases developed by

Roy Weatherby Roy Edward Weatherby (4 September 1910 – 4 April 1988), was the founder and owner of Weatherby, Inc., an American rifle, shotgun and cartridge manufacturing company founded 1945. Weatherby created an entire line of custom cartridges, and was ...

in the 1950s ( .378 Weatherby Magnum, .460 Weatherby Magnum). It can also be viewed as a shortened version of another .510 caliber cartridge based on the .378 Weatherby Magnum, the .500 A-Square (13x73 mm B) developed by

Arthur Alphin Lieutenant Colonel Arthur Brent Alphin (born September 5, 1948) is a retired United States Army officer and military historian. He is the founder and owner of A-Square, manufacturer of American hunting rifles. He taught military history at Wes ...

in 1976. The overall length of the loaded round is about which is identical to the .300 Winchester Magnum round to be able to fit magazines and actions of other common

belted magnum The term belted magnum or belted case refers to any cartridge, but generally a rifle cartridge, with a shell casing that has a pronounced "belt" around its base that continues past the extractor groove. This design originated with the British ...

rifles.

References

{{DEFAULTSORT:500 Whisper Pistol and rifle cartridges Whisper cartridges Subsonic rifle cartridges

Overview

Design

See also

References