Ok so long story short I'm sitting on an M3 I picked up second hand. My plan is to use it to convert some powder guys at the club during the monthly rimfire matches. These matches are basically bench style knock down silhouettes at 50, 100, 150, and 200m. Most, if not everyone there, is shooting subsonic 22lr so I would love to join in with some air powered 22 slugs. I guess my question is this... What do I need to do this? Where do I start? Long slug liner, a butt load of random slug sizes, and countless hours of testing?