10-22 although it's not always the most accurate off the shelf.
Put a Tactical Solutions barrel on it.
Vote Ruger 10-22 also... I've got a couple the kids have a couple, if you are into it you can upgrade the trigger yourself with a couple of stones and about $10 in springs from Brownell's. They are fun to work on!
Though Tactical Solutions is a step up from the average factory barrel for near the same money I would go with a Beyer, Kidd, or Fedderson Barrel on it, or for the least amount of money you could have 'Que' over at rimfirecentral set the factory barrel back & rechamber and crown it. Depends on what you are looking for.
Jerry