Pistol · Proprietary

6.5 JDJ

6.5mm JDJ

The 6.5 JDJ is a wildcat cartridge developed by J.D.

Caliber
0.264″ · 6.706 mm
Introduced
1978
Case
Rimless
Parent
.225 Winchester
Primary use
hunting, handgun_hunting
Status
Active
Velocity1,750–2,100 fps
Energy680–1,371 ft·lb
Identity
Introduced
1978
Type
Pistol
Origin
United States
Inventor
J.D. Jones
Manufacturer
SSK Industries
Standard
Proprietary
Status
Active
Availability
Rare
Build
Primer
Large Pistol
Case type
Rimless
Pressure & range
Max pressure
45,000 psi
Eff. range
200 yd
Max range
250 yd

Ballistics

Representative trajectory · 100 yd zero0–500 yd
100 yd · zero0″−79″79″ drop @ 500 yd0250500Open in Ballistic Compare ↗
Parent case
.225 Winchester

Representative trajectory — modeled from a single velocity input (no published BC for this cartridge yet).

Dimensionscase measurements · scale drawing · size vs familiar rounds

Case dimensions — the scale drawing at the top of the page is built from these.

reloading data · approximate
Measuremmin
Bullet ⌀6.710.264
Neck ⌀7.370.290
Shoulder ⌀10.390.409
Shoulder angle40°~
Base ⌀10.720.422
Rim ⌀12.010.473
Belt ⌀n/a
Rim thickness1.240.049
Neck length4.830.190
Case length48.261.900
Overall length68.582.700~

Size vs familiar rounds

Drawn at true 1:1 — every case is accurate relative to the others. Absolute size depends on your screen's pixel density, so measuring one against a real ruler may be off. 6.5 JDJ is highlighted below.

Reloading costestimate cost per round vs factory

Estimate your cost per round and how it compares to factory. Inputs are yours — nothing is stored.

Cost estimate only — not load data. Charge weight is your input; follow published manuals for safe charges.

Lineage

Immediate parent
Family TreeOpen 6.5 JDJ in the interactive cartridge family tree

Connected reference

History

Developed in 1978 as part of the SSK JDJ family of Contender cartridges, the 6.5 JDJ fills the gap between smaller varmint chamberings and larger bore hunting rounds on the Contender platform. It remains one of the more popular JDJ chamberings due to the 6.5mm bullet's excellent sectional density.

FAQs

What bullet diameter is 6.5 JDJ?
6.5 JDJ uses a 0.264″ (6.706 mm) diameter bullet.
Is 6.5 JDJ still in production?
6.5 JDJ is active; typical availability is rare.
What is 6.5 JDJ used for?
6.5 JDJ is primarily used for hunting, handgun_hunting.
What is 6.5 JDJ based on?
6.5 JDJ is derived from the .225 Winchester case.

Sources & provenance

Data & sources. Specs compiled from the Lindcott Armory reference; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →