Rifle · Not SAAMI standardized

.950 JDJ

24.1x70mm (approximate)

The most powerful sporting rifle cartridge ever made.

Caliber
0.95″ · 24.13 mm
Introduced
2005
Case
Rebated
Primary use
Target, Anti-Materiel
Status
Active
Velocity2,100 fps
Energy35,213 ft·lb
Typical grains2400 · 3600 gr
Identity
Introduced
2005
Type
Rifle
Origin
United States
Inventor
J.D. Jones / SSK Industries
Manufacturer
SSK Industries
Standard
Not SAAMI standardized
Status
Active
Availability
Rare
Build
Case capacity
1000 gr H₂O
Twist (typical)
1:24
Primer
50 BMG primer
Case type
Rebated
Pressure & range
Max pressure
45,000 psi
Eff. range
1000 yd
Max range
800 yd
Recoil
120–160 ft·lb

Ballistics

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

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

Performance

Best for HuntingSSK Industries FMJBT 2400gr2400 gr · FMJBT · 2,100 fpsBuy now →
Best for TargetSSK Industries Custom FMJ2400 gr · FMJ · 2,100 fpsBuy now →

Buy links open .950 JDJ ammunition at Rivertown Munitions.

Dimensionscase measurements · scale drawing · size vs familiar rounds

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

Wikipedia · approximate
Measuremmin
Bullet ⌀24.130.950~
Neck ⌀
Shoulder ⌀
Shoulder angle
Base ⌀29.161.148~
Rim ⌀26.921.060~
Belt ⌀n/a
Rim thickness
Neck length
Case length69.852.750~
Overall length101.604.000~

Missing a dimension for .950 JDJ? Some case measurements aren't in a published SAAMI/CIP drawing yet. Have a factory or reamer print? Send it → — verified hard-to-find data earns a free Lindcott sticker.

Factory loads

In production — 6 active loads across 2 brands. Top 6 shown.

BrandLoadGrainBulletFPSft·lbBC
SSK IndustriesFMJBT 2400gr2400FMJBT2,10023,497
SSK IndustriesCustom FMJ2400FMJ2,10023,497
SSK IndustriesSolid Brass 2400gr2400Solid Brass2,10023,497
SSK IndustriesSP Custom Factory Load3600SP2,10035,246
SSK IndustriesCustom Heavy3600FMJ1,90028,852
J.D. Jones/SSKCast Lead 3600gr3600Cast Lead1,90028,852

Velocities are manufacturer-stated (test-barrel). Discontinued loads dimmed.

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.

Connected reference

History

Developed in 2005 by J.D. Jones of SSK Industries, the .950 JDJ is the world record holder for the most powerful commercially produced sporting rifle cartridge. Only a handful of rifles exist, all custom-built. The cartridge uses .50 BMG primers and custom-made brass. The cost per round is several hundred dollars. The rifles require NFA registration as Destructive Devices if the bore exceeds 0.5" (which it does), making ownership and use highly regulated.

FAQs

What twist rate does .950 JDJ use?
.950 JDJ typically uses a 1:24 twist rate.
What bullet diameter is .950 JDJ?
.950 JDJ uses a 0.95″ (24.13 mm) diameter bullet.
Is .950 JDJ still in production?
.950 JDJ is active; typical availability is rare.
What is .950 JDJ used for?
.950 JDJ is primarily used for target, anti-materiel.

Sources & provenance

Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 6 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →