Hi mate,
I've got a set of butler creeks on mine;
eye is a 20, 1.775" (45.1mm). Obj is a 46, 2.430" (61.7mm)
i completely agree the butler creeks fail from time to time but found it hard to justify genuine Swaro ones at £60 a piece... £120 can replace a lot of butler creeks...
hope this helps
WH