It depends on what and where.
.22 - S&W 2206 for general plinking.
.22 MAG - Rossi 515 when poisonous snakes might be encountered
.44 SPL - Rossi 720 or Taurus 441 when a dangerous animal or human might be encountered
.44 MAG - S&W 329PD when a dangerous animal or human might be encountered and weight is a consideration
.45 LC - S&W 625MG when a dangerous animal or human might be encountered and weight isn't a significant consideration
