Atomicsaladbowl........ Ruger says not to shoot them in the 10/22 target model, not the standard 10/22. Same probably goes for most target .22's and stingers.
I didn't see the reason for not using Stingers in target guns, but it's because those guns have relatively short chambers, not providing enough space for the longer Stinger case to open, especially in an already dirty chamber. Pressures are not only much higher as the result, but accuracy also suffers.