If I am reading your story and there is a long section about your character playing an American football game, how relevant is it to the actual story? If paying this game has little relevance, please do not waste the reader's time wading through detailed description of moves in the game.
Would you like it if I wrote a romance and spent a thousand words of it about the playing of a shinty game?
In the same way, a few authors show how much they know about firearms by spending ages in description of what each weapon and type of ammunition can do. Is it relevant to the story? If the story is about a firearms-obsessed man, then yes, but if the weapons are a side isuue, then don't bother with all the unnecessary detail. You can display your expertise in a single paragraph, if you are a good writer.
The gist of the above is, please self-edit your writing to keep it to the story line. That will improve the tale.