Wissmach compatibility with Bullseye is a crap shoot. Compatibility is very difficult to do right. There is a reason Bullseye tests every tenth sheet – even though they are using the same recipe and manufacturing steps for every sheet.
I do not recommend using BE and Wissmach together unless you are willing to accept regular compatibility issues. When stuff breaks, and it will, you will have no one to turn to because neither company is in a position to support the other company’s glass.
Paul
FusedGlass.OrgHelios Kiln Glass StudioPaulTarlow.com