An MC that uses guns or more accurately a sniper~ It's k with any setting for eg. in a fantasy world or in a modern setting. Some eg. of this setting would be 'The Novel's Extra' In this case, the MC uses guns in the sense that he's a unique weapon user, which is always cool. Another eg. would be 'Release that Witch' And in this case, the MC doesn't really use the gun as much(as far as I've read), but instead his subjects and militia are the ones using it, which, again, is also cool. But the MC or anyone in this manner doesn't really use a sniper, so maybe not suggest something similar to this, please. So, all in all, I guess, recommend something or anything, where the MC uses guns(preferably a sniper look at prefix), please.
Maybe: Shadow Hero’s Everyday Life (fantasy, MC own a specialized wagic wand that modified to shaped & work like a sniper rifle when used) Megan to Dangan o Tsukatte Isekai o Buchinuku! (manga) Matan’s Shooter (KOR, VR game) Magic Bullet in Magic Land (dropped)