I've got a chrony, I'm still learning how to use it well. I'd be glad to shoot some.........might be a week or three before I get back out to shoot, it's getting close to bow season and most of my guns are ready. Now if only my shooting lanes were cleared!
I guess that you could ship someone about 5 rounds of ammo and have them chrony it. The load would have to be within specs of course. The elevation, temp and humidity would be a factor depending on where you live.
For the price of a couple boxes of ammo or a set of dies you could own your own Chronograph. They are cheaper than you might think, and will pay huge dividends later on down the road if you plan on reloading much.
I have had one for years and a must if you wildcat and reload regular ammo. As a general rule the fasted loads are not the most accurate. I just like the safety factor of knowing where I'm at for speed which can relate to pressure.
Have a great day.