Re: Sling on 15-22 - I used a canvas GI loop sling, and found that it worked well. I mounted the front on a picatinny mounted sling swivel (Midwest Arms, I think). I found that the detached rear loop style worked best for me in prone and sitting position. I used the "hasty" style loop in standing position, and found that I had to be careful not to get it too tight. If I did, I found that it tended to cause the rifle and pistol grip to cant, creating problems establishing and maintaining my natural point of aim.
Re: Is the 15-22 useful for a novice at Appleseed? Yes, I think the two most important points to consider are: 1. Is the rifle reliable. Make sure you've shot the rifle enough to know what ammo works and whether the rifle will function well enough not to distract from the learning experience. 2. The experience and results will be much enhanced by the installation of a good trigger. I originally started practicing with the stock trigger in my 15-22. The rifle was very reliable, but I wasn't getting the accuracy I wanted. I dropped in a Rock River 2-stage National Match trigger (easy installation) and that made all the difference in the world.
I think the light weight of the 15-22 and the adjustable butt stock should make this an excellent rifle for an young person or smaller adult beginner.
Be sure to practice with the rifle, know what ammo works best, have the rifle sighted in dead on at 25 meters (82 feet) and have at least two magazines.
I used the EOTech sight cowitnessed with the irons because my dominant shooting eye (right) simply won't focus on the front sight. I found that the red dot superimposed over the top of the front sight helped me with that. The red dot was small enough not to obscure even the simulated 400 yard silhouettes. It worked great during the cloudy weather, but faded out in bright sun, making me drop back to relying on the iron front sight.
Re: The Appleseed experience. I was somewhat sceptical at first of volunteer instructors, but I came away very impressed. The instructors were sincere in their beliefs, reasonable in their presentations and extremely knowledgeable about the fundamentals of marksmanship. They imparted the knowledge without any posing or egotism. I really enjoyed it, and learned a lot. My wife, who was a novice at shooting rifles, found it to be a great learning experience. She really progressed and improved her skills. Thanks to the lead instructors, BlueFeather, TaosGlock, LongRifle and NMMI.
My wife used a Ruger 10/22 set up with Tech Sights as a "Liberty Training Rifle". I think the 15-22 was every bit as useful and accurate as the 10/22.