NOT KNOWN DETAILS ABOUT SUPER177

I might definitely try out them. There may be not explanation that they might not perform just fine as part of your Beeman. I have had fantastic luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin etc.). I would consider a tin and find out how your Grizzly likes them as all guns seem to have their favored pellets.High quality amm