| .577/500 No. 2 Black Powder Express | |
| Origin: | United Kingdom |
| Type: | Rifle |
| Design Date: | Before 1879 |
| Case Type: | Rimmed, bottleneck |
| Bullet: | .507 |
| Neck: | .538 |
| Shoulder: | .560 |
| Base: | .641 |
| Rim Dia: | .726 |
| Case Length: | 2.83 |
| Length: | 3.40 |
| Primer: | Kynoch #31A |
| Bw1: | 300 |
| Vel1: | 1870 |
| En1: | 2340 |
| Bw2: | 340 |
| Btype2: | (factory load) |
| Vel2: | 1925 |
| En2: | 2800 |
| Balsrc: | "Cartridges of the World" [1] |
The .577/500 No. 2 Black Powder Express, also known as the 12.7mm British No. 2, is a British centerfire fire rifle cartridge.
The .577/500 No. 2 BPE was developed as a black powder round some time before 1879 by necking down the .577 Black Powder Express to .507-inches (12.9 mm)[2] for use in single or double rifles, as well as a variety of Martini-based lever rifles.
Like the .450 Black Powder Express, the .577/500 BPE came in several case lengths, the most common having a 3-inch case. A -inch variant would later be loaded with cordite to become the .577/500 Nitro Express.[1]
For some time the .577/500 No. 2 BPE was loaded with cordite to become the .577/500 No. 2 Nitro for Black, the same cartridge loaded with mild loadings of cordite, carefully balanced through trial to replicate the ballistics of the black powder version.[1]
The .577/500 No. 2 BPE was a popular cartridge in India for hunting all thin-skinned game up to tigers.[1] It did not face competition from comparable .450 rounds there in the decades following 1907 due to the ban on British military calibres. Like the .500 Black Powder Express, the .577/500 No. 2 BPE was never popular in Africa, not being powerful enough for thick-skinned game such as elephants.[1]
Moderately popular in its day, the round has long since ceased to be offered commercially.