It looks wrong to my eye but is it an optical illusion?I put a bubble level on top of the picatinny rail and a USO swivel and they matched up.Then removed the rail level and just used the USO at the 100 yrd range.I brought a carpenters level and drew a vertical line at 100 yrds and made sure the USO was level and put cross hair on vertical line and tightened it down.It groups about dime size all touching and at 200 yrds about a quarter.If it is canted at what distance would I notice it.Going out to 600 yrds in a couple of weeks what should I expect?