I always used Superdomes in my springers (mostly Webley Ospreys) and JSB Exact in my Daystate Huntsman. The Huntsman shoots JSB very well and is fair to terrible with anything else. Recently I started having poorer results with the Superdomes in the springers and switched to JSB, and I have to say the difference is quite marked, the JSB accuracy is phenomenal.

I was working on a Webley barrel recently and pushing a few pellets through it. Out of them all, the JSB differed from the rest in that both the skirt and the head fully engaged the rifling. The rest, including the Superdomes, seemed to have a smaller head diameter to "ride" on the rifling.

All in .177 by the way, .22 might be different.