There are a bunch of democratic senators out west and democratic representatives in the west and south who would be hurt politically by voting for any gun control measures. And their leadership knows it and they will not bring any bills forward that have the chance to cost them the majority.
They have much more pressing things to use the majority for and don't want to waste it on gun control.
Let's not forget that the number #1 job of all these congress persons is to get reelected anything that may cost them that opportunity usually will not be supported.
So we know that many anti-gun elected officials would love to tell us to turn them all in but there are enough pro gun officials to put the brakes on that idea. The republicans and not the second amendment took a beating in November. Sarah Brady would like you to think otherwise.
I am not advocating that we just assume the government will leave our guns alone. We should still actively fight to maintain our rights just not go crazy in the process.