>Got a 10/22, did an appleseed, made all the rookie mistakes.
Alright, kewl. You're not going into it blind.
Id recommend shooting a Rifleman score with the 22LR first. But if that's what you want to do, go for it!
I'd recommend getting a weighted workout bar and holding it in a standing offhand position for increasingly long times. A M1 Garand is much heftier than a 10/22. (-: