Lindcott Armory Rifle · Wildcat
6 BRA
The 6mm BR with a 40-degree Ackley shoulder, gaining slightly more case capacity and more consistent fire-forming than the parent 6mm BR.
- Caliber
- 0.2429″ · 6.17 mm
- Introduced
- 1978
- Case
- Rimless
- Parent
- 6mm BR Norma
- Primary use
- target, competition
- Status
- Active
- Introduced
- 1978
- Type
- Rifle
- Origin
- United States
- Inventor
- Benchrest community
- Manufacturer
- David Tubb / various
- Standard
- Wildcat
- Status
- Active
- Availability
- Specialty
- Case capacity
- 37 gr H₂O
- Twist (typical)
- 1:7.5
- Primer
- Small Rifle
- Case type
- Rimless
- Max pressure
- 55,000 psi
- Eff. range
- 1000 yd
- Recoil
- 6.5–10 ft·lb
Ballistics
Real trajectory computed from a representative load — Black Hills Gold Match OTM 105gr 105 gr, 2,850 fps, BC 0.272 G7 · 100 yd zero.
| Range | Velocity | Energy | Drop (in) | Drop (MOA) |
|---|---|---|---|---|
| 0 yd | 2849 | 1892 | -1.5″ | — |
| 100 yd | 2681 | 1676 | 0.0″ | 0.0 |
| 200 yd | 2519 | 1479 | -3.3″ | -1.6 |
| 300 yd | 2360 | 1299 | -12.2″ | -3.9 |
| 400 yd | 2209 | 1137 | -27.2″ | -6.5 |
| 500 yd | 2062 | 991 | -49.4″ | -9.4 |
| 600 yd | 1920 | 859 | -79.9″ | -12.7 |
| 700 yd | 1782 | 740 | -119.8″ | -16.3 |
| 800 yd | 1648 | 633 | -170.6″ | -20.4 |
Point-mass G7/G1 drag model, standard atmosphere — within ~2% of reference solvers to 1000 yd; real barrels and conditions vary. Open in Ballistic Compare →
Performance
Buy links open 6 BRA 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.
SAAMI · approximate| Measure | mm | in | ✓ |
|---|---|---|---|
| Bullet ⌀ | 6.17 | 0.243 | · |
| Neck ⌀ | 6.88 | 0.271 | · |
| Shoulder ⌀ | 11.68 | 0.460 | ~ |
| Shoulder angle | 40° | — | · |
| Base ⌀ | 11.96 | 0.471 | · |
| Rim ⌀ | 12.01 | 0.473 | · |
| Belt ⌀ | n/a | ||
| Rim thickness | 1.37 | 0.054 | · |
| Neck length | 8.18 | 0.322 | ≈ |
| Case length | 38.86 | 1.530 | ~ |
| Overall length | 68.58 | 2.700 | ~ |
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 BRA is highlighted below.
Factory loads
In production — 20 active loads across 14 brands. Top 15 shown · see all 20 →.
| Brand | Load | Grain | Bullet | FPS | ft·lb | BC |
|---|---|---|---|---|---|---|
| Black Hills | Gold Match OTM 105gr | 105 | OTM | 2,850 | 1,893 | 0.272 G7 |
| HSM | Benchrest 105gr | 105 | OTM | 2,850 | 1,893 | 0.272 G7 |
| Norma | Match HPBT 105gr | 105 | HPBT | 2,850 | 1,893 | 0.527 G1 |
| Berger | HPBT Benchrest 105gr | 105 | HPBT | 2,850 | 1,893 | 0.527 G1 |
| Sellier & Bellot | OTM Match | 65 | OTM | 3,150 | 1,432 | — |
| Norma | OTM Benchrest | 65 | OTM | 3,150 | 1,432 | — |
| Lapua | OTM Benchrest | 65 | OTM | 3,150 | 1,432 | — |
| RUAG Ammotec | Swiss P HPBT 90gr | 90 | HPBT | 2,950 | 1,739 | — |
| RWS | Classic | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
| Sellier & Bellot | SP | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
| PPU | Standard | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
| Wolf | FMJ | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
| Norma | Classic | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
| Kynoch | Classic | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
| Buffalo Arms | Custom | 68 | Hollow Point Boat Tail | 2,950 | 1,314 | — |
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.
Lineage
Connected reference
History
As the 6mm BR Norma gained traction in F-Class and benchrest competition, shooters began fire-forming the brass to an improved shoulder for marginally better performance and brass life. The 6 BRA became a well-established benchrest cartridge in its own right and is recognized as the developmental ancestor of the 6mm Dasher.
FAQs
- What twist rate does 6 BRA use?
- 6 BRA typically uses a 1:7.5 twist rate.
- What bullet diameter is 6 BRA?
- 6 BRA uses a 0.2429″ (6.17 mm) diameter bullet.
- Is 6 BRA still in production?
- 6 BRA is active; typical availability is specialty.
- What is 6 BRA used for?
- 6 BRA is primarily used for target, competition.
- What is 6 BRA based on?
- 6 BRA is derived from the 6mm BR Norma case.
Sources & provenance
- StandardSAAMI — SAAMI cartridge & chamber drawing — 6 BRAarchived
- StandardSAAMI — ANSI/SAAMI Z299 — Cartridge & Chamber Drawingsarchived
Data & sources. Specs compiled from the Lindcott Armory reference; availability counted from 20 live factory loads; the trajectory is modeled (point-mass), not measured. See methodology. Spotted an error? Report it →