Lindcott Armory Pistol · Proprietary
.309 JDJ
The .309 JDJ is a larger SSK JDJ cartridge based on the .444 Marlin case necked down to .30 caliber.
- Caliber
- 0.308″ · 7.823 mm
- Introduced
- 1979
- Case
- Rimmed
- Parent
- .444 Marlin
- Primary use
- hunting, handgun_hunting
- Status
- Active
- Introduced
- 1979
- Type
- Pistol
- Origin
- United States
- Inventor
- J.D. Jones
- Manufacturer
- SSK Industries
- Standard
- Proprietary
- Status
- Active
- Availability
- Rare
- Primer
- Large Pistol
- Case type
- Rimmed
- Max pressure
- 42,000 psi
- Eff. range
- 250 yd
- Max range
- 300 yd
Ballistics
- Parent case
- .444 Marlin
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 · verified| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 7.82 | 0.308 | ✓ |
| Neck ⌀ | 8.53 | 0.336 | ✓ |
| Shoulder ⌀ | 11.58 | 0.456 | ✓ |
| Shoulder angle | 40° | — | ✓ |
| Base ⌀ | 11.94 | 0.470 | ✓ |
| Rim ⌀ | 13.06 | 0.514 | ✓ |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.60 | 0.063 | ✓ |
| Neck length | 8.69 | 0.342 | ≈ |
| Case length | 56.52 | 2.225 | ✓ |
| Overall length | 51.05 | 2.010 | ✓ |
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. .309 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
Connected reference
History
Developed by J.D. Jones in the late 1970s, the .309 JDJ is built on the .444 Marlin case to allow larger powder capacity than the smaller JDJ designs. It is a serious deer and hog cartridge in Contender or Encore pistol form.
FAQs
- What bullet diameter is .309 JDJ?
- .309 JDJ uses a 0.308″ (7.823 mm) diameter bullet.
- Is .309 JDJ still in production?
- .309 JDJ is active; typical availability is rare.
- What is .309 JDJ used for?
- .309 JDJ is primarily used for hunting, handgun_hunting.
- What is .309 JDJ based on?
- .309 JDJ is derived from the .444 Marlin 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 →