I had a look into this a while ago for my archery blaster and its possible to get close to 45%, fiddled about in mids and got 44%. Only downside is it means you have to pick up weave, stealth, CJ and only 1 epic power can be picked.
I changed the Archery bit to AR and can post the build that i made. Im sure someone could improve it in some way though 
Hero Plan by Mids' Hero Designer 1.401
http://www.cohplanner.com/
[url=http://www.cohplanner.com/mids/download.php?
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A765981163C419238C04639431C64831A619C78CEE6FEB8E11  F4]Click this DataLink to open the build.