Our 6mm is a Remington 700, but my son and I have whacked a lot of rock chucks and other varmints with it over the years.
For deer, we usually use a 95 gr Nosler Ballistic Tip loaded over RE-22. Excellent accuracy and excellent terminal results on mule deer.
For rock chucks, we've bounced around a lot in the loads over the years. Usually one of the 75 gr hollow point bullets from Sierra or Speer, loaded over H4350. That load has worked out really well, and will really drop 'em hard.
H4350 and RE-22 have been the powders I've relied on the most with that cartridge. At least in recent years.
I've used bullets as light as 55 grains on varmints, and they worked okay, but weren't as accurate as the 75 - 100 grain bullets from my rifle. The little 60 grain Sierra hollow point though - that's an accurate little rascal. One thing the 55's have going for them is muzzle velocity... Can really crank 'em up.
Haven't ever used the 65 gr V-Max you wrote of, likely because I started varminting with the 6mm long before that bullet came on the scene. I'd expect it to perform well though.
Regards, Guy