OK, so I've been playing with Lock'nLoad for a few days, trying to figure some at least reasonable ballpark figures for things like range, and it struck me that I really have no idea what the muzzle velocity of my mortar is.
I'm not really all that excited about trying to convince my father that I need to borrow his chronograph in order to do it. I don't feel like buying him a new one when I inevitably blow it to smithereens due to some small misalignment between it and the bore of the mortar.
My idea is that the next time I shoot it, I accurately measure the time from firing to impact. Since I'll know the barrel elevation to the nearest degree, and I know the weight of the projectile (7000 grains, +/-), and I know the shape and dimensions of the projectile (blunt cylinder, diameter 2.9"), I can calculate the BC fairly accurately. I won't really care about the range at first, all I'm interested in is time to impact. That should allow me to use Lock'nLoad to find a velocity, given the known parameters, that matches the time of flight that I observed. I'd just keep adjusting the velocity until the time of flight matches. Given that, I can then set about generating a reasonably accurate set of elevation X = range Y with charge Z tables
Of course, I'm going to have to average several shots with closely matching projectiles and powder charges, and I'll have to measure the temp, pressure, humidity, elevation above sea level, and latitude at the time of firing.
So, is my thinking off base here, or is this a sound method to get a reasonable estimate of muzzle velocity?