Love 3 groove barrels personally. Doesn't mean they are the best though but odd grooves keep me happier for some reason.
I sure might be tempted to go to 10 twist though, gives you a better shot at the 68/69/70 grain bullets if you ever need to stretch its legs some.
Of course if you are convinced you'll only be shooting light bullets, regardless to wind drift or distance issues, 12 is just fine.
Were I to go 12 twist with those bullets I"d be looking at flat base bullets for great accuracy. And 60 Sierra flat base HPs are cheaper and never any slouches.
Final line, if you really want a 222, no reason not to do it. Pleny of us want something for some personal reason, when there are better, IOHO, options.
Jeff
