Robert Bartley Hopler Jr., of North Richland Hills, Texas, passed peacefully surrounded by the love of his family on Tuesday, February 20, 2024.

Bob was born on March 3, 1932, and grew up in Madison, New Jersey. After high school he attended college on an ROTC scholarship at the Missouri School of Mines, in Rolla, his keen interest in math and science having led him to the study of engineering. There he met Helen (Gaddy), the love of his life. Over the years they made their home in a number of states and traveled widely. They were married 66 years, until Helen passed in 2021.

Between earning BS and MS degrees in Mining Engineering, he proudly served in the U.S. Army Chemical Corps. Bob enjoyed his days as an instructor in the handling of military explosives, toxic gases, and flame throwing. Upon leaving active duty, he served as a Company Commander in the Army Reserves, leaving with the rank of Captain.

He had 35 years of experience in explosives industry, including 24 years in R&D, technical service, and project and product management with Hercules Incorporated prior to the acquisition of Hercules’ Explosives Division by Dyno in 1985. In the 1960’s he was instrumental in the introduction of bulk slurry to mines in Minnesota, Michigan, Wyoming, California, and Panama. He was project manager for the R&D and introduction of the Hercudet nonelectric detonator system in the U.S., Canada, and Japan from 1974 to 1984.With Dyno he had product management responsibilities prior to his assignment as Manager of Corporate Technical Service.

Prior to Hercules, his work experience included summer work as a miner in an underground zinc mine in New Jersey, and work as a miner at a gold dredge in Alaska. After obtaining his bachelor’s degree, he worked as a mining engineer and shift supervisor with the St. Joe Lead Company in underground lead mines in Missouri.

He is a Legion of Honor (50 year) member of SME of AIME; is an Emeritus member of the Society of the Sigma Xi; he belonged to IABTI and was a member and Board Secretary for ISEE. He has served as chairman of the Technical Committee of IME; was a member and subcommittee chairman of the National Academy of Sciences committee on tagging explosives; and served on a Lawrence Livermore National Laboratory committee on “Reducing the Ambiguity and Visibility of Signals from Mining Activities,” in support of the Comprehensive Test Ban Treaty. Mr. Hopler testified on the properties of ANFO to the McVeigh grand jury in the Oklahoma City bombing case. He served on the NFPA Technical Committee on Explosives. He served on the Safety & Health Committee of the National Coal Association/National Mining Association, and participated in meetings of the UTRC (Underground Technology Research Council). He was Executive Director of DEDA (the Dyno Explosives Distributor’s Association) from 2001 to 2010.

In addition to authoring some 90 technical papers or presentations on explosives, he contributed “Explosives 100 Years Ago” in the Journal of Explosives Engineering since the magazine’s initial issue in May 1983.A compilation of the articles was published by ISEE in 2001 as “Explosives 100 Years Ago, More or Less - The Book.” He was technical editor of the 17th Edition of the ISEE Blasters’ Handbook. He contributed the initial chapter entitled “The History, Development, and Characteristics of Explosives and Propellants” in both the first and second editions of the book “Forensic Investigation of Explosions.” He was the compiler and editor of histories of the IME. In 1999 he appeared on television in the History Channel presentation entitled “Dynamite.”

He has taught classes and made presentations on explosives at the FBI Academy, the FAA Technical Center, and various ATF and IABTI meetings.

He held 6 US patents and 19 associated foreign patents on various aspects of explosives and mining technology.

Bob retired in 1996 from his position as Manager of Corporate Technical Service for Dyno Nobel Inc. in Salt Lake City, Utah. After retirement he started the companies The Old Powderman – Books and Powderman Consulting, Inc.

Lifelong hobbies included woodworking, photography, astronomy, book and stamp collecting. He also had a DIY mentality that knew no bounds- no home or car repair was beyond him. He used an electronics kit to build a color tv, then built it into the family room wall, a marvel in the early 1970s. He took photographs of the 1970 solar eclipse, using a telescope he built himself.

Bob is survived by daughter, Jennifer Ann Haas of Farmington, Minnesota; daughter, Karen Elizabeth Boyer and husband Ken of North Richland Hills, TX; grandchildren, Alex Haas, Madison Haas, Samantha (Boyer) Alderson and husband Kit and great-grandson Emmett; step-grandson Dylan Boyer and wife Tracy.

He is preceded in death by his wife Helen; his parents Robert B. Hopler Sr. and Margaret Hopler; his sister Marilyn Brown and husband Frank, nephew Cliff; and step-grandson Matthew Boyer.

His memorial service will be held at 11:30am on Saturday, March 23 at Center Point Church, North Richland Hills, Texas.