Designer J.D. Jones
Case type Rimless, bottleneck
|Place of origin United States|
Parent case .30-06 Springfield
Bullet diameter .197 in (5.0 mm)
The .30-06 JDJ is a modified .30-06 Springfield cartridge designed to be used in the Thompson Center Arms Contender single-shot pistol. The idea behind it is to replicate the ballistics of a .30-06 fired from a rifle in a Contender pistol.
Currently, the .30-06 JDJ is not offered by any manufacturers. Cases and bullets for it can be purchased from various companies for handloaders.
Compared to a default .30-06 round, the .30-06 JDJ contains has a smaller neck that is at a 60-degree angle. However, the biggest difference is that the .30-06 JDJ has little body taper compared to the original .30-06 cartridge. This allows the .30-06 JDJ to hold an extra 5 grains of water (4.875 cm3) compared to the .30-06 Springfield, allowing one to put more gunpowder into the cartridge.
This round manages to replicate in a pistol the ballistics of a .30-06 round fired from a rifle. For example, a .30-06 JDJ cartridge with a 200-grain bullet fired from a custom Contender has a muzzle velocity of 2,504 ft/s (763 m/s), while a regular .30-06 cartridge with a 200-grain bullet with 55 grains of gunpowder has a velocity of 2,558 ft/s (780 m/s).