Bad advice from military/law enforcement...
I see it a lot on these forums and I hear it all the time at the gun shop where I work: "My friend is in [the military/law enforcement] and he says..."
Sometimes it's good advice, and often it's bad or even terrible advice. But whatever the advice, it's usually taken as gospel based solely on the fact that the friend has military or law enforcement experience, and that's a mistake.
I want to caution newer shooters in trusting the gun advice of people solely based on their military/law enforcement experience. Those institutions don't necessarily teach anything more than just how to use the specific weapons one is issued; general firearms knowledge is rarely taught. Being a former Marine who spent four years in an infantry MOS, I can tell you that the Marine Corps only teaches you how to use weapons; general firearms knowledge is usually completely irrelevant, especially pertaining to civilian weapons.
Sure, there are many current and former military/law enforcement personnel who have received advanced training and are also well-versed in civilian firearms. But there are also a lot of those who don't have advanced training and haven't studied up on civilian firearms at all, yet present themselves as firearms experts just because of their military/law enforcement experience.
So while some of the best training and advice I've received has come from current and former military/law enforcement, some of the worst firearms advice I've ever heard has also come from the same kind of people.
0331: "Accuracy by volume."