The 6mm BRA (6mm BR Ackley Improved) is a highly regarded wildcat rifle cartridge that has gained popularity among precision rifle shooters, particularly in PRS and long-range competitions. Derived from the 6mm BR Norma, the 6mm BRA features an improved 40-degree shoulder angle and slightly less body taper, increasing its powder capacity to around 40–41 grains of water. This enhancement allows it to push 105–110 grain bullets at velocities near or exceeding 2900 feet per second, providing a flatter trajectory and reduced wind drift compared to its parent cartridge. Despite its increased performance, the 6mm BRA maintains the outstanding accuracy and efficient burn characteristics of the 6mm BR. The cartridge requires fireforming standard 6mm BR brass, a straightforward process that slightly expands the case to its new dimensions. One of the major appeals of the 6mm BRA is its balance between speed, recoil, and barrel life—offering better ballistics than the BR while remaining milder than larger 6mm rounds like the 6mm Creedmoor.
Though not standardized by SAAMI or CIP, it is widely supported in the precision shooting community with ample load data shared among reloaders. Overall, the 6mm BRA stands out as a top-tier performer for competitive shooting disciplines.
Suitable Powders
Bullet Weight (gr) -> | 0-50 | 50-75 | 75-100 | 100-150 | 150-200 | 200-300 | >300 |
|---|---|---|---|---|---|---|---|
👍 ... suitable powder
👍👍 ... suitable AND popular powder among our reloading community (clasification might evolve as more community members share their loads )
Caliber Specifications
Standard / Datasheet
Primer Size
Large Rifle (LR)
Max. Case Length
40.5 Grains of Water
Bullet / Barrel Diameter
0.243'' | 6.17 mm
Max. Case Length
1.56'' | 39.62 mm
Max. Cartridge Length
2.32'' | 58.93 mm
Max. Standardized Pressure:
60191 psi | 4150 bar
XXL ID
CID_184
6 mm BRA load data is available with the following bullets:
(most popular first)
