I might unquestionably check out them. There's not purpose that they would not perform just fine in your Beeman. I've had very good luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin and so forth.). I'd try out a tin and see how your Grizzly likes them https://super17713333.blogginaway.com/36682997/5-simple-statements-about-super177-explained