UPDATE:

Back from the range today. Here is the results of firing the 5 loaded cartridges. see target below. This first outing was with fire-forming loads. According to loading data for the 376 Steyr, shown in the book, African Dangerous Game Cartridges, by Pierre van der Walt, I assume the 9.5 Peterlongo cartridge will be capable of matching the performance of the 376 Steyr, which is capable of 2870fps with a 235g bullet, 2600fps with a 270g bullet, and 2500fps with a 300g bullet.

Also shown is a comparison of different cartridges and their case capacity in terms of grains of water.

375 Whelen .... 74.5g H2O
9.3x62 Mauser ..... 74.8g H2)
9.5x60 Mauser ..... 78.2g H2O
376 Steyr ..... 79.3g H2O
9.5mm Peterlongo ..... 84.0g H2O
9.3x74R ..... 84.2g H2O
375 Taylor ..... 87.9g H2O

http://www.buckstix.com/buckpi...ETERLONGO-TARG-0.jpg