"raise to.."
just say this. There is no confusion here.
I actually make a point of saying what I"m going to do before I count out my bet/raise. That way my intention is clear before I"ve touched any chips and If I miscount, get colours mixed up, string bet them in, drop them etc there is no problem.
I think will"s idea of not speaking and just putting the chips in can be a mistake (especially when putting a single chip in, that would be enough for a raise, counts as a call)