AFTE Store - Bullet Identification From H&K USP Polygonal Barrels

The Heckler and Kock ( H&K) Universal Self-Loading Pistol (USP) was initially equipped with cut-rifles barrels having a 6 groove, right twist. A subsequent marketing change in 1994 replaced the cut-rifled barrels with the cold hammer-forged polygonal barrel also twisting 6 right. Because of the potential bullet identificaiton problems associated with polygonal rifling, a study was undertaken to determine the feasibility of identifying fired bullets from an H&K USP caliber .40 S&W polygonal back to the barrel of orgin. After collecting and examining 30 sets of test fires, this examiner believes that even the polygonal rifling now marketed in the H&K USP .40 S&W, Identifying bullets to barrels of origin is no more difficult than in situations involving the more common cut-rifled barreling.