I don't think using 110 to 120 grains of triple 777 in a cva eclipse mag is such a good idea. I use to own one when I first got back into BP,and do have to say the gun was a tack driver.I myself just did not care for the plastic stock but hate to part with it ,it always shot clover leaf groups at the 100 yd target. I think the manual states 100 grains of loose powder and 150 grains pellets,think you would be pushing 120 grains of the 777 powder.
My load was 110 grains of pyrodex select and a QT'S 40 240 grain precision bullet/sabot/
I do remember it would not shoots pwerbelts to save it life.