There are no pictures of this, only in your mind.....from Edger Rice Burroughs in "A Princess of Mars" as described by the character John Carter:
"These rifles were of a white metal stocked with wood, which I learned later was a very light and intensely hard growth much prized on Mars, and entirely unknown to us denizens of Earth. The metal of the barrel is an alloy composed principally of aluminum and steel which they have learned to temper to a hardness far exceeding that of the steel with which we are familiar. The weight of these rifles is comparatively little, and with the small caliber, explosive, radium projectiles which they use, and the great length of the barrel, they are deadly in the extreme and at ranges which would be unthinkable on Earth. The theoretic effective radius of this rifle is three hundred miles, but the best they can do in actual service when equipped with their
wireless finders and sighters is but a trifle over two hundred miles."
Adds a new dimension to extreme long range shooting but I don't know how these 15 foot tall green men are able to shoot past the curvature of Earth..er Mars.