:.950 JDJ
{{short description|Large caliber rifle cartridge}}
{{infobox firearm cartridge
|name=.950 JDJ
|origin=United States
|type=Rifle
|service=
|used_by=
|wars=
|designer= J. D. Jones
|design_date=
|manufacturer=SSK Industries/Knight Rifles
|production_date=
|number=
|variants=
|is_SI_specs=
|parent= 20×102mm Vulcan
|case_type=
|bullet= {{convert|0.950|in|mm|abbr=on}}
|neck=
|shoulder=
|base=
|rim_dia=
|rim_thick=
|case_length= {{convert|2.75|in|mm|abbr=on}}
|length=
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|rifling=
|primer=
|max_pressure=
|max_cup=
|filling=
|filling_weight=
|detonation=
|yield=
|is_SI_ballistics=
|bwunit=
|bw1=3600
|btype1=
|vel1=2200
|en1=38685
|bw2=
|btype2=
|vel2=
|en2=
|bw3=
|btype3=
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|image=file:950caliberJDJ.jpg|caption=A .950 JDJ}}
The .950 JDJ (24.1×70mm) is a powerful large caliber rifle cartridge developed by American gunsmith and weapon designer J. D. Jones of SSK Industries.
Cartridge
Rifles
As its name implies, rifles chambered for the cartridge have a groove diameter of {{convert|0.950|in|mm|abbr=on}}. SSK received a "Sporting Use Exception" to de-regulate the rifles. Thus, in the United States, they can be owned like any other Title I rifle by an American citizen at age 18. The rifles use stocks and extraordinarily thick Krieger barrels bearing an {{convert|18|lb|abbr=on}} muzzle brake.{{cite book|last=Barnes|first=Frank C.|title=Cartridges of the World: A Complete and Illustrated Reference for Over 1500 Cartridges|url=https://books.google.com/books?id=02CYCAAAQBAJ&pg=PA416|edition=14th|date=19 December 2014|publisher=F+W Media, Inc.|location=Iola, Wisconsin|isbn=978-1-4402-4265-6|page=416}} Overall, depending on options, the rifles weigh from {{convert|85|to|120|lb}} and are therefore only useful for shooting from a bench rest or heavy bipod.[http://www.securityarms.com/20010315/galleryfiles/2200/2289.htm McBros 95 caliber rifle single-shot bolt-action rifle], Securityarms.com Despite the weight, recoil is significant and shooters must be sure to choose components (i.e., scopes and bipods) that can handle the force. The sheer size, weight, and power of these rifles make them rather impractical for hunting use. SSK only manufactured three of these rifles and as of 2014 no longer produces the ammunition.{{cite book|last=Rottman|first=Gordon L.|title=The Big Book of Gun Trivia: Everything you want to know, don't want to know, and don't know you need to know|url=https://books.google.com/books?id=wZ0eDAAAQBAJ&pg=PT288|year=2013|publisher=Bloomsbury Publishing|isbn=978-1-78200-950-4|page=288}}
Ballistics
The cartridge propels its {{convert|3,600|gr|0|abbr=off}} bullet at approximately {{convert|2,200|ft/s|m/s|abbr=off}}. This yields a muzzle energy of {{convert|38,685|ft.lbf|J|0|abbr=off}}.{{cite web|url=http://soldiersystems.net/2014/02/25/ssk-industries-950-jdj-largest-centerfire-rifle-ever-made/|title=The SSK Industries .950 JDJ – The Largest Centerfire Rifle Ever Made|year=2014|publisher=SoldierSystems }}
By comparison, the 5.56×45mm NATO cartridge, used in the M16 and M4 rifles, produces between {{convert|1,200|-|1,300|ft.lbf|J|abbr=off}}, while the .308 Winchester, a favorite for hunters, police, and military snipers, produces between {{convert|2000|-|3000|ft.lbf|J|abbr=off}} depending on the load used. Even the .50 BMG, which has a kinetic energy of around {{convert|13,000|-|15,000|ft.lbf|J|abbr=off}} delivers less than half the energy. The ballistics of the .950 JDJ are more similar to that of the 20 mm autocannon round, which delivers approximately {{convert|39500|ft.lbf|J|abbr=off}}. The muzzle energy of the .950 JDJ is comparable to the kinetic energy of a {{convert|2800|lb|abbr=off}} automobile traveling at {{convert|20|mph|km/h|abbr=off}}.
In a {{convert|110|lb|abbr=on}} rifle, this will develop well over {{convert|200|ft.lbf|J|abbr=off}} of free recoil energy. Shooting usually involves a heavy "lead sled" or similar shooting rest, and the rifle scope has significant eye relief to avoid injuring the ocular orbit.{{citation needed|date=October 2020}}
References
{{reflist}}
External links
- [https://www.youtube.com/watch?v=qg0RdhFnTd0 "Fat Mac" - SSK Industries' .950 JDJ Rifle] Forgotten Weapons
{{DEFAULTSORT:950 JDJ}}
Category:Pistol and rifle cartridges