A shock wave is a discontinuous change in pressure and density, obtained only through hard impact or from a detonation. (A step function, not a Dirac delta, which is not a physical process.) Neither are present in regular firearms or airguns. There may be a response to pressure loads, but they are not "shock." And common experience shows that they are no hindrance to high accuracy of such mediocre projectiles as spheres (BBs). I've had occasion to instrument a solid propellant rocket motor to track down an actual shock wave transient in its ignition process. We needed to have a transponder that had a time resolution of about 1 millisecond (1000 Hz). This is nothing like that. The practical reality (as I mentioned) is that there is no such problem with airguns.
You are making it up as you go along. First, the scope will be noticed, but not the pistol. Now, the scope will be noticed so much that the pistol will also be noticed? Why don't we agree that a competent assassin will take pains to conceal what he is doing? There is no question that the scope will help him hit his target point. (I am a shooter and hitting anything within a hand at 50 feet is not easy with iron sights.)
I happen to be a retired aeronautical engineer, who knows a lot about shock waves in tubes (graduate research and production engineering). I also have a long background in firearms information. You happen to be a guy with a little bit of knowledge, who is reaching wrong conclusions.
Then you would know it would be pointless to try to impart rotation to a needle. Any perturbation and the needle would twist and rotate like a propeller (preferred rotation axis aligned with maximum moment of inertia). And you would also know that there is nothing wrong with aerodynamically stabilized projectiles (like arrows) which are capable of considerable accuracy. And you would know that a sabot could be made of (e.g.) fibrous materials that would self-shred upon expulsion from the muzzle, after separation from the needle (or call it a flechette). You would know all these things and would not argue against them. You would know that if the assassin were to use a pistol, or a silenced pistol, it would be the same operational scenario requiring concealment. You would know that a modest sight magnification would greatly assist any targeting at distances of 50 feet or so. You would know all these things.
But do you? You certainly do not know what a shock wave is. Or that there are no such phenomena even internally to a firearm. Or that the velocity attainable from a gun system is proportional to the speed of sound in the propellant gas (which is why hot hydrogen gas guns are used to project high-altitude sounding projectiles).
I apologize for any insult to your professional standing, but you must realize that you should have known these things.
A shock wave is a discontinuous change in pressure and density, obtained only through hard impact or from a detonation. (A step function, not a Dirac delta, which is not a physical process.) Neither are present in regular firearms or airguns. There may be a response to pressure loads, but they are not "shock." And common experience shows that they are no hindrance to high accuracy of such mediocre projectiles as spheres (BBs). I've had occasion to instrument a solid propellant rocket motor to track down an actual shock wave transient in its ignition process. We needed to have a transponder that had a time resolution of about 1 millisecond (1000 Hz). This is nothing like that. The practical reality (as I mentioned) is that there is no such problem with airguns.
You are making it up as you go along. First, the scope will be noticed, but not the pistol. Now, the scope will be noticed so much that the pistol will also be noticed? Why don't we agree that a competent assassin will take pains to conceal what he is doing? There is no question that the scope will help him hit his target point. (I am a shooter and hitting anything within a hand at 50 feet is not easy with iron sights.)
I happen to be a retired aeronautical engineer, who knows a lot about shock waves in tubes (graduate research and production engineering). I also have a long background in firearms information. You happen to be a guy with a little bit of knowledge, who is reaching wrong conclusions.
Then you would know it would be pointless to try to impart rotation to a needle. Any perturbation and the needle would twist and rotate like a propeller (preferred rotation axis aligned with maximum moment of inertia). And you would also know that there is nothing wrong with aerodynamically stabilized projectiles (like arrows) which are capable of considerable accuracy. And you would know that a sabot could be made of (e.g.) fibrous materials that would self-shred upon expulsion from the muzzle, after separation from the needle (or call it a flechette). You would know all these things and would not argue against them. You would know that if the assassin were to use a pistol, or a silenced pistol, it would be the same operational scenario requiring concealment. You would know that a modest sight magnification would greatly assist any targeting at distances of 50 feet or so. You would know all these things.
But do you? You certainly do not know what a shock wave is. Or that there are no such phenomena even internally to a firearm. Or that the velocity attainable from a gun system is proportional to the speed of sound in the propellant gas (which is why hot hydrogen gas guns are used to project high-altitude sounding projectiles).
I apologize for any insult to your professional standing, but you must realize that you should have known these things.