Script error </th></tr>
.950 JDJ
Type Rifle
Place of origin22x20px United States
Production history
DesignerJ. D. Jones
ManufacturerSSK Industries
Parent case20 × 102 mm Vulcan
Bullet diameter0.950 in (Bad rounding hereScript error mm)
Case length4 in (Bad rounding hereScript error mm)
Maximum pressure8,349,768 psi (Bad rounding hereScript error MPa)
Ballistic performance
Bullet weight/type Velocity Energy
3,600 gr (Script error g) 2,200 ft/s (Bad rounding hereScript error m/s) 38,685 ft·lbf (Bad rounding hereScript error J)

The .950 JDJ is a large caliber rifle cartridge developed by J. D. Jones of SSK Industries.


Loaded .950 JDJ cartridges are approximately the length of an empty .50 BMG casing (i.e., 4 in orBad rounding hereScript error cm), and are based on a 20×102mm case shortened and necked up to accept the .950 in (Bad rounding hereScript error mm) bullet.[1] Projectiles are custom-made and most commonly weigh 3,600 grains (Bad rounding hereScript error g) which is 8.2 ounces or over half a pound.[2]


As its name implies, rifles chambered for the cartridge have a bore diameter of 0.950 in (Bad rounding hereScript error mm), which would normally classify them as Destructive Devices in the United States under the 1968 (1934) National Firearms Act. However, SSK sought and received a "Sporting Use Exception" to de-regulate the rifles, meaning they can be purchased like any other Title I rifle by a person over age 18 with no felonious criminal record.Script error[citation needed] The rifles themselves, of which only a handful have been made, use McMillan stocks and extraordinarily thick Krieger barrels bearing an 18 lb (Bad rounding hereScript error kg) muzzle brake. Overall, depending on options, the rifles weigh from 85 to 110 pounds (Expression error: Unrecognised punctuation character "[". to Expression error: Unrecognised punctuation character "[". kg) and are therefore only useful for shooting from a bench rest or heavy bipod.[3] Despite the weight, recoil is significant, and shooters must be sure to choose components (i.e., scopes and bipods) that can handle the abuse. The sheer size and weight of these weapons makes them impractical for hunting use, as they cannot be carried afield. Thus, they are largely "range queens"—rifles that are brought to the range for a fun time, but not usually used for hunting or other "more practical" uses. Additionally, the cost of owning and operating such a firearm is beyond most shooters; the rifles cost ~US$8,000, loaded cartridges are $40 each, and the individual lathe-turned bronze bullets are $10 apiece.[4]


The cartridge propels its 3,600 gr (Bad rounding hereScript error g) bullet at approximately 2,200 ft/s (Bad rounding hereScript error m/s). This yields a muzzle energy of 38,685 ft·lbf (Bad rounding hereScript error J)[1] and a momentum of 154.1 Newton-seconds, about the same as a 20x102mm Vulcan round.Script error[citation needed] This kinetic energy would allow the .950 JDJ to pass through several body-armored humans. It is comparable to the original tank rounds of World War I in terms of ballistics.Script error[citation needed]

By comparison, the 5.56×45mm NATO cartridge, used in the M16 rifle, produces between 1,200–1,300 ft·lbf (Expression error: Unrecognised punctuation character "[".Expression error: Unrecognised punctuation character "[".Expression error: Unrecognised punctuation character "[". Expression error: Unrecognised punctuation character "[".), while the .308 Winchester, a favorite for hunters and medium-range police/military sniping, produces between 2,000–3,000 ft·lbf (Expression error: Unrecognised punctuation character "[".Expression error: Unrecognised punctuation character "[".Expression error: Unrecognised punctuation character "[". Expression error: Unrecognised punctuation character "[".) depending on the load used. The ballistics of the .950 JDJ is more similar to that of the 20mm autocannon round, which delivers approximately 39,500 ft·lbf (Bad rounding hereScript error J). The muzzle energy of the .950 JDJ is comparable to the kinetic energy of a 2,800 lb (Bad rounding hereScript error kg) automobile traveling at 20 mph (Bad rounding hereScript error km/h).

In a 110 lb (Bad rounding hereScript error kg) rifle, this will develop well over 200 ft·lbf (Bad rounding hereScript error J) of free recoil energy if an efficient muzzle brake is not used. This is far beyond the shoulder-firing capacity of nearly all humans, even without considering the difficulty of shouldering such a heavy rifle. Shooting is usually heavy "lead sled" or similar shooting rest, and the rifle is not held to the shoulder because of the severe recoil and possible injury. The rifle scope has significant eye relief to avoid injuring the ocular orbit.

See alsoEdit


  1. 1.0 1.1 McBros .95 caliber rifle, Airborne Combat Engineer.
  2. Rifle ..., SSK Industries.
  3. McBros 95 caliber rifle single shot bolt action rifle,
  4. "950 jdj" thread, forums at Pistolsmith.Com.

External linksEdit

Ad blocker interference detected!

Wikia is a free-to-use site that makes money from advertising. We have a modified experience for viewers using ad blockers

Wikia is not accessible if you’ve made further modifications. Remove the custom ad blocker rule(s) and the page will load as expected.