I am good for about 50 a year, thats plenty enough for me these days. I don't shoot them all with "Handi rifles" only but have neen using the Handi Hornet some the last year.
One note on the .204 caliber. Basically, it's very loud and some of your new farms may not appreciate the loud muzzle blast as in the summer, windows are open,people outside,etc. I would seriously consider going the walking woodchuck route rather than the long distance having played both games allot. Make a pair of shooting sticks and take to field a 22 Hornet or Rimfire Magnum. Those calibers keep you in the fields. You will likely find if you start hunting certain farms on a regular basis that, the owners are not going to feel comfortable with that high powered rifle big boom out on the back acerage, when they are out and about during spring & summer.
The walking game is more challenging and you get more action to boot. It's not real sporting shooting woodchucks inside 250 yards with a .204,22-250,.243 etc from prone with a bi-pod or bag and by far most your shots will be inside 200 unless you want to set up your location for long distance and wait,wait,wait.
If you hit a farm hard in a season or two, you will want to skip it the next two season and rotate or you will wipe out the woodchucks in that area. To hunt woodchucks avidly year after year as I do, you will need to continue gaining access to new farms on a regular basis and let some shots pass or you whipe them out. You learn to "manage" the fields and enjoy the outdoors to keep it going rather than look for big numbers in a season and then have nothing the next year or two.
The most challenging shots to make are standing off hand at 75-100 yards. That shot is harder than the 400-500 yard from prone with bi-pod & rear bag,big scope,heavy barrel laser stick,hot rod caliber and laser range finder.
Shooting from sticks sitting out to 150 yards (head shots) with a rim magnum (I luv my 17hmr for such on chucks with TN'T ammo) or simular with a 22 Hornet on upper body shots, along with walking a hedge row looking for jump shots from standing is the most enjoyable way to hunt woodchucks and the farm owners feel much more comfortable with the low muzzle blast.
You don't need a laser range finder and all that stuff. Just grid it off as you pace the field and make note.
This and a rim mag or hornet is all you need. I made my sticks from Varmint Al's site and there is a photo of them there also.