In my experience, 22" is about the cut-off for where I notice the muzzle blast. That is the only thing that would weigh on my mind. That is one reason I don't like shooting AR15s.
You will do fine by the 308 but it is a little excessive for ground hogs. If you have a $750 budget I wouldn't get hung up on the fact that you already have dies.
If I were to buy a new walnut stocked 308 right now it would be a Ruger Hawkeye. American made, reliable as anything you can buy off a shelf and aesthetically pleasing. Guess what, it has a 22" barrel.
