.30-06 JDJ

The .30-06 JDJ is a firearm cartridge designed by J.D. Jones.

Overview
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.

Description
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 taper compared to the original .30-06 JDJ 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.

Ballistically, the .30-06 manages to replicate the ballistics of a .30-06 round fired from a rifle well. For example, a .30-06 JDJ cartridge with a 200-grain bullet fired from a custom Contender has a muzzle velocity of 2504 ft/s (762 m/s), while a regular .30-06 cartridge with a 200-grain bullet with 55 grains of gunpowder has a velocity of 2558 ft/s (779 m/s).