Esri announced this last week, so some of you may have already seen it, but they have posted feature layers with select tables from the 2013-2017 ACS. These are sourced directly from the Census Bureau's API. The data are available for free through ArcGIS online, though they do not include block group level data.
Read more about it here:
https://www.esri.com/arcgis-blog/products/arcgis-living-atlas/announcements/mapping-american-community-survey-acs-data-just-got-easier/