Wow guys and girls!!! Didnt expect that kind of response. I know they can be pretty high in cost since they stopped making the .5mm I think back in 1974 or around there. I know there were roughly 15,000 sold totalby Remington. I have found all the centerfire conversion kits and brass, bullets, dies, etc, but I dont use the gun enough to convert it especially when converting costs more than the gun is worth. Ill look at the sites you guys and gals listed and see what I can find. I have a buddy in Kentucky who thinks he may beable to get a box of shells for around $20.00-$40.00 Hes goign to look today. Thanks again.