I have shot it with a Sig 556 (the first time I went) and just missed a Rifleman score. A fair number of people shoot centerfire, the main drawbacks are ammo cost and if you're not used to the recoil it can potentially make it harder to diagnose any technique problems you have. I enjoyed shooting mine and will likely shoot a centerfire again at a future Appleseed at some point. The only drawback for me is ammo price and availability of 5.56 right now.
You will need anywhere from 200-500 rounds depending upon the pace of your particular event and whether you take some courses of fire off or not. I think I shot in the 350-450 range the two times I went.
There have been two or three 308 WIN rifles at each of the two events I went to, but keep most people shooting centerfire seem to have AR or AK variants. You could take both a rimfire and centerfire and switch at some point, start with the rimfire and switch once you have the instruction and technique down.
You can use a bolt action, just make sure it has a removable mag or you will have trouble getting loaded within the time limits. It's also a bit harder to maintain your natural point of aim while working the bolt, but I have seen it done well and would like to try it at some point.
Last edited by shanzlik; June 19, 2013 at 06:23 PM.