I might surely test them. You can find not cause that they'd not perform just high-quality as part of your Beeman. I've had excellent luck with RWS pellets in all of my airguns (Hatsan, Crossman, Benjamin etc.). I would try a tin and see how your Grizzly likes them as https://super17701000.blogacep.com/41309895/the-best-side-of-super177