It's alright
I love this Zoom sight on his Mahcine Pistol - I don't imagine now is a good time to mention that it's typically a short range weapon, no I didn't think so, so I won't mention it....
Animation wise, I'm not a fan of stick figures - a very small number are animated well, but the vast majority (like this) makes it look more like you were too lazy to draw even a cartoon character.
On top of that you need to work on your explosion animations, and if you're going to have an extreme close up of a rifle barrel - you might as well take the effort to animate a muzzle flash - especially considering you can't see the rifle round leaving the barrel.
Not too bad, but consider spending a little extra time to tidy it up and not settle for "oh that's good enough for now" - Even if your not a good artist - your work will benefit from spending more time on it.