As always, it's contextual though it's fairly simple to understand the premise.
If there is no way for another player to see that you are visibly armed because your player is performing an action that hides said weapon, then yes. It is exploiting.
If you're all about the roleplay, my suggestion would be to perhaps try with a flare gun, get yourself dressed up to look the part and let your voice do the rest! Providing you provide high quality roleplay from the start, if police arrive, they should at least give you a chance to play out your roleplay story.