I have a savage with a .28 sts engine in it and i went to start it a run it in fir the first time, started up great first time and then about after 30 secs or so the revs started to blip and then all of a sudden they shot up to full throttle carb was only about 1mm open, has anyone had this problem or know what the cause could be.

try this thread
STS .28 Engine Thread

happened to me too. thankfully only once. I suspect an air leak in my tanks primer.