SIG SAUER P320 pistol

New Hampshire-based SIG Sauer makes the P320 9mm handgun is shown in this 2017 file photo.

CONCORD — New Hampshire gun maker SIG Sauer is facing another proposed class-action lawsuit involving claims the company’s P320 pistol can fire without the trigger being pulled.

The complaint, filed Friday in federal court in Concord on behalf of Arizona gun owner Derek Ortiz, claims the P320 pistol has a design flaw allowing it to discharge if dropped. The lawsuit claims the Newington-based company continued to sell the gun even after discovering its potential for malfunction.