For really pumping out the .22lr, get a Calico Carbine...100-rds per mag tops anything else on the market...
if you're going to do it, do it RIGHT!!
Slide-fire stocks are a waste of cash...go get a Wii & Link's Crossbow Trainer,
Train Daily and you'll quickly learn to pull triggers with Jerry Miculek-like speed.
Aiming like him is another matter of intense training