OP - If you want shooting with a challenge then go with the 22 L.R. But be advised it will not be an easy nor inexpensive trip. First of all if you want to go with a 22 at 100 yards you need to decide if it is going to be a sporter style (off the shelf type hunting rifle) or if you want a true benchrest rifle that is pretty much unsuited for anything besides shooting off of sandbags.
No matter which you choose to go with a good trigger is a necessity. I have a couple of 22's that are capable of shooting one-inch 5 shot groups at 100 yards as long as I read the wind correctly, have good follow through and basically do everything exactly the same for 5 shots.
If you do decide to go with a 22 L.R. my advice is to start at 50 yards, when you can consistently shoot 1/4 - 3/8 inch 5 shot groups at 50 yards then step out to 100 yards. You will find shooting one-inch groups at 100 a real challenge, it takes the a combination of a good shooter, a good wind reader, and good ammo that your rifle thrives on (one of the biggest challenges is finding the ammo that the rifle shoots best).
I prefer sporter rifles since I like to be able to use them for hunting and plinking also, the most inexpensive rifle I have that is capable of one-inch groups at 100 is a Tikka T1X, the other is a Cooper 57M Jackson Hunter. The Tikka is around $500 the Cooper about three times that much but it is more consistently accurate and less prone to having an occassional flyer.
drover
