I'm really interested to see how this story unfolds, I think it has a lot of potential but there are a few things you might want to brush up on to really give your work a professional edge.

There are a few typos in you summary, I'm almost certain you meant 'desert solider' instead of [dessert soilder]. Also saying that you're new to fictionpress and this is you first story can be off-putting to people - you want to sell yourself and your story as best you can!

Your dialogue is really good, I don't think you need the big paragraph about Maxton's appearance (we don't need to know he's EXACTLY 171 pounds, do we?). I'd really like to see more dialogue and have the dialogue describe him. The flashback seems to happen kind of randomly, I was hoping to find out more about the man Maxton was with and the prank they were pulling (I also don't think you meant it was a 'vulnerable' prank, as that doesn't really make sense.). Also, referring to each gun by it's model, make and calibre isn't always necessary. Especially since your story is set in the future, they will probably have different/ better guns in 21 years.

There are a few redundancies, like ["Shhhh!" The first mercenary shushed] and [It was called the Electromagnetic Twirler because it was an Electromagnetic Twirler]. 'Shhh' already implies that he was shushing someone, so adding [The first mercenary shushed] isn't needed. As I have no idea what an Electromagnetic Twirler is, you should probably have more description of what it is, or at least just leave it at [It was called the Electromagnetic Twirler] .

Not trying to be negative, I think you have a good writing style. A few changes would really improve it though. Update soon!