Inflation moderated in April but was still close to its highest level in 40 years.

Daniel Defense, the company that made the rifle a gunman used to kill 21 people inside a Texas elementary school this week, was one of hundreds of gun makers and merchants that got emergency small-business aid from the federal government through the Paycheck Protection Program.

The company, based in Ellabell, Ga., received a $3.1 million loan in early April 2020 — just days after the relief fund opened, when many companies were struggling to…