Guided homing smart projectiles? Sights allowing the guided homing. Lasers? Caseless ammo. The case dissolving onfiring, gases down the barrel or out an ejection port. Fuel injection instead of powder? Fuel or gas ignition would allow very short bolt stroke, only the need to changed the projectile, andno large ejection port as no case.

Such are my science fiction mental writings.

But do t worry, we in Australia won't see any of this. Well still be using bolt action rifles. Those of class will still be using double and single shot rifles of 200 years of age.

All off topic. I've never seen such as scope as on this thread. Though I've seen modern prismatic style scopes I think. But without that long bar in front.