>>30639There's not many, and as for why it's time for some politics and anthropology.
Japan doesn't have an army. It has a "Self Defence Force" that's (since WWII) explicitly not for going to war. Like the US navy, the entire Japanese armed forces are in more danger at home than when they're on active duty. Thus it's perceived as being filled with adorable but ineffective nerdy man-children. See the column "Japan's cute army", or the animu GATE.
Secondly, japan has very strict gun control. Civilians can't own them, and policemen can't use them without facing an enquiry. There's a real case where a policeman shot himself, and was posthumously prosecuted for misuse of his firearm, in order that his actions might rightly bring shame to his family.
The upshot of this is that in Japan, guns are not cool. The only people that have them are nerdy, beardy old guys who collect deactivated weapons and don't use them for anything because they're deactivated.
In Japan, guns are uncool. Gun enthusiasts are Japan's trainspotters.
What is cool is toy guns like airsoft, which fill the same role in pop culture as real guns would in the USA (minus having to be a redneck, terrorist or school-shooter). People with airsoft guns can and do actually use them for stuff.
This is why there are so many mangos and animus about airsoft, and so few about real guns.