I agree with Mr. Brinkmeier's answer. However, I've also seen a probate take much longer if the estate attorney takes their time or something else comes up in the meantime to hold things up. You can also write or call the probate clerk where the Will is being probated in GA and ask about its status, since its a public record.
I am not admitted to the Bar in the state of Georgia and I suggest that you contact an attorney who practices in the probate courts in that state.
In the event that your brother began a probate, in virtually all states he would have to file or lodge the will with the court so it would be relatively easy for you to read the will. (By the way, the probate would logically be filed in the state in which your grandfather lived which I assume is Georgia).
While thirty days seems like a long time, it is not that long. On the other hand, do not delay with your research, Consider taking action quickly.