Assuming he sticks to the rhetoric in his victory speech (that he'll stick to the least divisive issues) he probably won't try anything more extensive than magazine size limits, which will likely fail.
Even the multiple long-gun reporting thing for the south-west was met with fanatical resistance, and that's about as mild as national gun control measures get. So long as the Republicans control the house or senate, our guns are safe from legislation.
As for the SCOTUS, the 2nd amendment has already been defined to include personal defense, and precedent has accordingly been set. The supreme court rarely reverses decisions once they're made.
Not that we should be complacent, but our guns are reasonably secure for the moment.