Lindcott Armory Pistol · Obsolete / Non-standard
4mm Übungsmunition
German WWII indoor training cartridge fired through a sub-caliber insert installed directly inside a standard service pistol.
- Caliber
- 0.1791″ · 4.55 mm
- Introduced
- 1940
- Case
- Rimless
- Primary use
- Training
- Status
- Obsolete
- Introduced
- 1940
- Type
- Pistol
- Origin
- Germany
- Inventor
- German Ordnance Department
- Manufacturer
- German State Arsenal
- Standard
- Obsolete / Non-standard
- Status
- Obsolete
- Availability
- Collector Only
- Case capacity
- 1.2 gr H₂O
- Primer
- Small Pistol
- Case type
- Rimless
- Max pressure
- 12,000 psi
- Eff. range
- 25 yd
- Max range
- 30 yd
- Recoil
- 0.1–0.3 ft·lb
- Subsonic
- Capable
Ballistics
- Parent case
- —
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.
mixed/other · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 4.55 | 0.179 | ~ |
| Neck ⌀ | 4.86 | 0.191 | · |
| Shoulder ⌀ | 5.52 | 0.217 | ~ |
| Shoulder angle | 14.2° | — | ~ |
| Base ⌀ | 5.52 | 0.217 | · |
| Rim ⌀ | 5.66 | 0.223 | · |
| Belt ⌀ | n/a | ||
| Rim thickness | — | — | |
| Neck length | 2.80 | 0.110 | ≈ |
| Case length | 6.60 | 0.260 | ~ |
| Overall length | 9.08 | 0.357 | · |
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. 4mm Übungsmunition is highlighted below.
Factory loads
In production — 5 active loads across 4 brands. Top 15 shown · see all 20 →.
| Brand | Load | Grain | Bullet | FPS | ft·lb | BC |
|---|---|---|---|---|---|---|
| RWS | M20 Lead RN | 6 | Lead RN | 600 | 5 | — |
| RWS | Lead RN Gallery | 6 | Lead RN | 600 | 5 | — |
| RUAG Ammotec | FMJ Training 6gr | 6 | FMJ | 590 | 5 | — |
| Bundeswehr | FMJ Training Military | 6 | FMJ | 590 | 5 | — |
| DAG | FMJ Training 6gr | 6 | FMJ | 590 | 5 | — |
| Geco | Lead RN Gallery | 6 | Lead RN | 600 | 5 | — |
| Buffalo Arms | Custom | 8 | Lead Round Nose | 600 | 6 | — |
| Wolf | FMJ | 8 | Lead Round Nose | 600 | 6 | — |
| Norma | Classic | 8 | Lead Round Nose | 600 | 6 | — |
| RWS | Classic | 8 | Lead Round Nose | 600 | 6 | — |
| Sellier & Bellot | SP | 8 | Lead Round Nose | 600 | 6 | — |
| PPU | Standard | 8 | Lead Round Nose | 600 | 6 | — |
| Armscor | Standard | 8 | Lead Round Nose | 600 | 6 | — |
| Kynoch | Classic | 8 | Lead Round Nose | 600 | 6 | — |
| Hirtenberger | FMJ Training 6gr | 6 | FMJ | 590 | 5 | — |
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
The Wehrmacht faced a training ammunition shortage as WWII progressed — live 9mm Parabellum was too valuable to burn on stationary target practice, and dedicated training ranges were being destroyed by Allied bombing. German ordnance engineers developed a steel insert that fit inside the barrel and chamber of the standard Walther P38 and Luger P08, reducing the bore to 4mm. Soldiers loaded the insert, chambered a 4mm cartridge, and fired — experiencing the actual trigger, grip, and sights of their service weapon. The tiny 4mm projectile had just enough energy to penetrate a paper target at 10-15 meters. The system was later adapted for rifles and submachine guns. It represents one of the most ingenious training ammunition solutions ever devised: zero retraining on a different weapon, zero cost of a separate training pistol, and usable in any bombed-out basement.
FAQs
- What bullet diameter is 4mm Übungsmunition?
- 4mm Übungsmunition uses a 0.1791″ (4.55 mm) diameter bullet.
- Is 4mm Übungsmunition still in production?
- 4mm Übungsmunition is obsolete; typical availability is collector only.
- What is 4mm Übungsmunition used for?
- 4mm Übungsmunition is primarily used for training.
Sources & provenance
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 5 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →