God help me, but I actually understand this scientific paper, and it actually answers my question...
 

"Method of Measuring the Ballistic Coefficient of Bullets"

I just bought a chronograph (this one), and have been playing with it. I shot a string of ten shots through it with the Airsoft pistol (Average velocity = 307.7 fps, SD = 4.76, in case you're interested) I bought a while ago (to pop the feral cats that my mother wanted me to dissuade from hanging around our bird feeder), because that's easy and not as dangerous as shooting my real (airgun and firearm) guns for the purpose. Main reason I bought the chrono was to A) establish the distance to sight-in the real ones at to achieve my desired point-blank range, and B) determine how powerful they really are. Both of those questions require knowing the actual velocity of your projectiles (they also require knowing your bullet mass, but I already have a scale that measures that to 0.01 grams, so not an issue). They also require knowing the actual "Ballistic Coefficient" of those projectiles. I wanted to know if one could determine the BC (because most bullet-sellers won't actually tell you that, or else give you unreliable bullshit numbers if they do) if one knows the muzzle velocity and an instrumental velocity from some known down-range distance. So I googled it. And got this scientific paper. And understood it. :jaw: Yeah, the BC is calculable from two [distance,velocity] knowns. And everything else I want to know is calculable from that. You can calculate the entire trajectory of your bullet from muzzle to the point it crashes into the ground. No need to fire and measure the experiment (after the first two that you measured, of course).

The paper was written by a bunch of Russkies, though. Should I be thinking "Marko Ramius", Iosef Djugashvili (atmittedly a Georgian rather than a Russian), or Nikolai Ivanovich Lobachevsky (is his name, HEY!!!)???

Can you cock that high end pellet gun yet?

Barely. I shot a couple of shots thru the chrono and got about 940 fps.

I just shot another 10 with it. One gave 1257, which was ridiculously out of the expected range, so I don't know what went wrong, but toss that one, anyway, and one [ERR 3] (projectile not recorded by the 2nd sensor), so toss that one. I got 8 good shots. Velocity = 931.1 FPS, SD of 8 shots 3.98.

The guys in the videos using/cocking one make it look easy. I can barely manage to cock that damn thing. But I can. The targets downrange blow up nicely for being shot with an air gun. They actually come close to looking like I'd hit 'em with a .22LR. This air gun is almost as good, but legal and safe to shoot where I bought the damn thing for. I'm happy with my purchases... both the gun last fall and the chrono this spring. Both are lovely toys I'm gonna enjoy playing with.

So. Can you chronograph a spud launcher with it?

Probably. It supposedly will do anything between 5 feet per second and 9999 feet per second. In other words, anything between a medium-fast walk, and well over the velocity of an M1 Tank main gun. Of course, you have to hit within the uprights, and that tank gun will break your crono if you try to fire over it.

Now, getting back to why I looked at (and resurrected) this thread: I just ran my (now "Ex") favorite .177 pellet rifle thru the chrono, and found out why I keep missing. When I get a good shot in, it's a good hit. When I miss, it's "Why the fuck did I miss such an easy shot???" Let's look at the figures, eh?:

1) 601
2) 601
3) 581
4) 433
5) 526
6) 250 <:jaw: [damn, how did that happen?]
7) 512
8) 206 <:jaw::foil: [damn, that's even worse...]
9) 315
10) 341

Inshallah... Bend it down and break it.

Or maybe you could spill a little oil on the action...