I was writing my war story, and realized that there was a lot of military jargon in it. Big surprise. Specifically, I began to consider that a lot of people aren't in the military, so the subtleties of certain words and their weight might not be obvious to readers. I'll list examples below for you to give advice, but am eager to just hear your thoughts on controlling the effects of 'insider' language in a story. Pointman, contact, suppression, echelon, skirmisher, vic, grenadier, trooper, NCO, mic, webgear, flak, fatigues, task force, displace, vector, mark, billet.
I understand most of those terms (at least, I think I do) and I'm not in the military. It's more important to support your jargon with context so people can figure it out, and not to go too overboard with frequency and density--use it to add distinctive flavor, but don't overdo the spice.
Yep, for most people that would be good advice. But it also depends on what you want to achieve. In my WIP I use military jargon which is self-explanatory from context, but has been used in real war. It therefore has a whole lot of undertones, only accessible to the readers who have either read memoirs or have been in there. And I embrace these unacknowledged levels, that is as it should be. I could also write a different style, aimed at education and exactness. If done like that, my WIP would be a completely other story. For the casual reader, casual context should give him an idea what you are talking about.
Have you read any military books? Most of them include a short explanation for the more obscure terms, or acronyms that the reader might not get, like NCO. Most of those terms are pretty generic and easy to figure out, so you should be okay; if you're in doubt, have someone who's got no experience read over it and see what they think.