Several things I would suspect...First, you are close to being underspined....In fact, you are. That could be part of it. Another part of the equation is simply this.....The farther away you are from your target the more difficult it is to hit, and groups open up. Third, you may have a tuning issue....but to be honest, sitting here there is NO WAY I could tell you for sure.

I will say this......Last summer I was practicing for season, and was shooting Magnus Stingers w/ Blazers from 70 yards....I was consistently hitting a 2" square w/ that combo....Do Blazers work, you better believe it.