Just wondering everyone's opinion since I have been seeing this a lot lately. I have seen many players with a stack size of 9-15 big blinds opening (especially under the gun) with a raise amount of 1/3 or half their stack. I know on face value this looks like it is a very strong raise since they are betting less than all in because they want a call but I am wondering if players are doing this as a bluff more often than not?

The hands I have seen go to showdown have been generally split between strong hands and hands that are not good enough to shove but too good to fold (suited and unsuited broadways). Any thoughts on this if you use it as bluff tactic or when you see it happen what your initial thoughts are at the table?

It's always difficult to answer such a question with little information to go on. There are so many other factors to consider. However, based on the scenario you laid out I would take the play at face value, basically, and assume it was not a bluff but a weak move by a player with a not-good-enough-to-shove hand. A shove would make more sense simply to reduce the number of potential callers. I've seen this play called by more than one player. After the flop our hero is out of position in a multi-way pot. They usually check and fold to a bet at that point.

I dont think, this is a fundamentally sound strategy, and therefore I am not really worrying about, why people do it, or with what kind of hands. If you face it, you need to consider it an effective shove and continue with the same range, as if they had made an actual shove.