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.950 JDJ cases are approximately 70 mm in length, and are based on a 20×110mm case shortened and necked up to accept the .950 in (24.1 mm) bullet. Projectiles are custom-made and most commonly weigh 3,600 grains (230 g) which is 8.2 ounces or over half a pound.
As its name implies, rifles chambered for the cartridge have a groove diameter of 0.950 in (24.1 mm). SSK received a “Sporting Use Exception” to de-regulate the rifles. Thus, in the United States, they can be purchased and owned like any other Title I rifle by an American citizen at age 18. The rifles use McMillan stocks and extraordinarily thick Krieger barrels bearing an 18 lb (8.2 kg) muzzle brake.Overall, depending on options, the rifles weigh from 85 to 120 pounds (39 to 54 kg) and are therefore only useful for shooting from a bench rest or heavy bipod. 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, 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.
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