Power limits, the magic number

[CharlesHarris]

That magic number 671 fps works very well for specialized low-noise small game cartridges we sometimes call "cat sneeze", for their mild report when fired in a rifle.

Over the weekend I fired some antique rook rifles which were rescued from the UK before they were butchered into shotguns, and many surviving specimens have been, being converted to .410 bore so that they could remain legal.

One was a Cogswell & Harrison in .380 Rook, which was rechambered to use .38 Special target wadcutter ammunition. The other was an Army & Navy in .450 revolver, which shoots .455 OK.