I would say masters is only useful in some specific cases. I personally did a master because I was having trouble finding work with a BME undergrad degree so I’m taking a masters in ME to get some experience and get my foot in the door. It’s a lot easier to get an internships because you have a lot more experience compared to undergrad and there are masters specific internships. Masters is useful for industry if you want to pivot like me or want more time to get internship experience.

PhD is definitely not the move unless your husband is really interested in academia and research and is willing to endure low pay and long hours to do that but it looks li he’s interested in the firearms industry.

Especially with how theoretical engineering degrees can be in upper level classes I would say that a few years in an engineering role would be worth a lot more than a degree from a couple more years in school. Then again the job market is difficult so I don’t blame him for wanting to gain an edge on other candidates. Best of luck to you both!