Don’t laugh but been trying many pellets to try to match those larger 22 prewar barrels. Best has been as many have said JSB Superdomes. Tried some Gamo Match Diablos 15.43 grains really fill the barrel. Works with Haenel 28 and BSA Standard. Not as well made but the key with the Haenel 28 is filling up that barrel and fulling engaging the rifling.