Our Mission
At Stronghold Corp, we are a full-service gun shop and firearms training company committed to helping you find the right equipment—and develop the right skills—for your mission. Founded by lifelong firearms users and Second Amendment advocates, we only offer products we would trust with our own lives. From firearms and ammunition to accessories and NFA items, our inventory reflects our uncompromising standards for quality and reliability. Our instructors have been providing professional firearms and use-of-force training since 2002. With experience operating in federally regulated environments, we hold ourselves to a significantly higher standard than the industry minimums. At Stronghold Corp, our training programs are backed by decades of real-world expertise and a deep commitment to safety, responsibility, and excellence. We would be honored to be your choice for firearms training. Even if you don’t train with us, we strongly encourage you to carefully research any instructor you consider. When you hire a firearms instructor, you’re entrusting someone to teach you life-saving skills—make that decision wisely. If you have questions or want to learn more, we’re here to help.
John Schwertfeger
President & Co-Founder
Read more
Josh Embretson
Vice President
Read more
John Schwertfeger
John Schwertfeger is a seasoned security professional with over three decades of experience in military, law enforcement, nuclear security, and private sector training. A native of Southeast Iowa, John began his career in national defense by enlisting in the United States Air Force immediately after high school. He completed both the USAF Security Police Law Enforcement Academy and the Air Base Ground Defense School, and was assigned to the 55th Security Police Squadron at Offutt Air Force Base in Nebraska.
During his time at Offutt, John was recognized as the 1996 Law Enforcement Airman of the Year. He served on the 55SPS Emergency Service Team and trained with the Omaha Police Department’s Emergency Response Unit. He deployed three times to the Middle East, where he conducted force protection, critical asset security, and dignitary protection missions. His military service earned him numerous awards, including the Air Force Commendation Medal, Air Force Achievement Medal, Southwest Asia Service Medal, National Defense Service Medal, Armed Forces Expeditionary Medal, and others recognizing his exemplary performance.
Following his honorable service, John transitioned to Retail Security, specializing in loss prevention, covert surveillance systems, access control, and DEA-regulated pharmaceutical monitoring. In 2000, he joined the commercial nuclear security field at the Duane Arnold Energy Center (DAEC) in Palo, Iowa. Over a 22-year career at DAEC, John served in a range of roles, including several years in security training and ultimately as Security Manager. He was instrumental in leading vulnerability assessments, strategy development, Force-on-Force evaluations, and interagency coordination with local, state, and federal law enforcement.
John is an NRA-certified Tactical Handgun and Patrol Rifle Instructor, H&K USP armorer, and AR-15 rifle armorer. He has been an active member of national-level industry working groups, including the U.S. Nuclear Regulatory Commission’s Enhanced Weapons Pilot Program.
In 2013, John co-founded Stronghold Corp with longtime business partner Josh Embretson. Based in Northeast Iowa, the company focuses on delivering professional-grade firearms training and tactical equipment to civilians, law enforcement, and critical infrastructure personnel.
Since the closure of DAEC in 2022, John has devoted his efforts to expanding Stronghold Corp’s training programs and consulting services. He provides strategic security guidance to critical infrastructure sites in the U.S. and partner nations and continues to develop innovative physical security products to meet evolving threats.
John’s expertise includes small arms and tactics, security force management, fixed facility defense design, surveillance systems, vehicle barrier planning, and adversary simulation program development.
Josh Embretson
Josh Embretson is a seasoned professional with over two decades of leadership experience in nuclear security, armed security operations, and training program management. His career spans 19 years at the Duane Arnold Energy Center (DAEC), where he held progressive roles in security leadership—from Armed Security Officer to Security Operations Supervisor—culminating in his oversight of more than 120 armed personnel during the plant’s operational and decommissioning phases.
In 2013, Josh expanded his expertise by becoming Vice President of Stronghold Corp, a federally licensed (FFL Type 1 and Type 7) firearms and tactical solutions company. At Stronghold, he leads strategic operations and works directly with customers to provide tailored firearms and security solutions and specialized firearms services, including NFA items under SOT licensing.
Throughout his tenure at NextEra Energy, Josh demonstrated a strong commitment to operational excellence and training innovation. As Security Training Coordinator, he developed and implemented comprehensive training programs for armed nuclear security officers, oversaw instructor performance, ensured adversary teams (OPFOR) effectiveness, oversaw all firing range operations, managed performance testing programs and ensured compliance with NRC and federal standards.
Josh holds a Bachelor’s degree in Criminal Justice from St. Ambrose University, where he was a standout student-athlete. He earned All-American honors as a punter and participated in an NFL free-agent tryout, showcasing his discipline and drive both on and off the field.
He is also a certified NRA Law Enforcement firearm Instructor, Certified Commando Krav Maga instructor, certified Glock Pistol Armorer, Certified AR15 Armorer, has attended Barrett M82 Armorer course, attended M249 Armorer courses, is experienced in physical security system design, and proficient in interfacing with federal agencies and compliance bodies such as the NRC and the ATFE.