This is a discussion on Open raising range? within the online poker forums, in the Cash Games section; How much does your open raising range gets affected when you have limpers behind? does it get more wide or does it narrow?
I personally tighten up my range against limpers, I raise draw heavy hands with a big raise and I raise smaller with premium hands hoping to get the OL to call, but that depends on how many people are going to call my raise, if its just the open limper, then the above is what I would normally go for.
If too many people call raises after cold calling I will more than likely not raise with AK especially OOP, I would raise bigger with my premium hands to narrow the field, it all depends on position and what reads I have