Unfortunately, it's same ole, same ole.
Mass shooting occurs. Public outrage ensues. Democrats attempt reform. NRA sends out, "Thoughts and Prayers." Republicans proclaim that "Guns don't kill people - people kill people" - and that the answer to gun violence is that "A good guy with a gun will stop a bad guy with a gun." Nothing changes.
Given the massive partisan divide in the USA and the somewhat equal proportion of Republican versus Democratic voters in the States - the only way, IMO, that gun control is likely to pass is that a slight Democratic majority in both the House and Senate exists at some point as well as a Democratic president - and that the filibuster rule in the Senate is thrown out. Only then might gun control legislation pass both houses. Even then, the Supreme Court is stacked with a super-conservative majority (meaning that they could lose 1 conservative vote and still prevail) - so whatever legislation that's passed is probably going to be deemed "unconstitutional."
I'm coming up on my 60th (sigh) birthday. Likely I'll die in my 80's. In the short span of years left to me - do I think that gun control legislation will both pass in the States and will withstand legal challenge - no fucking way.