6mm br

What Size Bullet would be considered the Minimum weight for Deer and what would be the smallest powder column? This would be for a viable Hunting Cartridge. Would something the size of a 6mm PPC be sufficient?

Hate to do it but my running and gunning days are over. Looking to send my rifles to a good home. The BR has a fresh chamber for 105s and the 260/30 has a brand new barrel with only the load development done. (Think it was 45.6 gr of 4350, 0.020" off, etc). That cartridge runs a 130gr Berger...