How is this data calculated
There are 3 ways to obtain this ballistic data
1 - Doppler Radar
This is very precise of course and can measure the entire bullet flight path - however its extremely expensive and requires a large area to actually work - our colleagues supplied this radar to the NZ Army - It is a big brother of the Labradar
2 - Drop Scale Calibration
You fire a series of shots at the distances required and make adjustments to the ballistic data to make the results fit.
This requires you to be able to reliability shoot consistent groups at the ranges required, it consumes a lot of time, is affected by variations in weather, you abilities, scope variations and consumes ammunition.
You need to fire enough to ensure you performed the test correctly to get good data; you need good measurements to get good data - is the target 900 metres, or 897m.
You should measure all the factors at the same time, including velocity.
You should not be adjusting the muzzle velocity (that is a known measurable data point) but only the BC.
To give you a idea on how hard this is (and you need to fire enough rounds), at 1000m a SD of 18 fps can give a 5 inch vertical uncertainty and just getting the range wrong by 5m can also induce another 6 inches of vertical uncertainty - right there is 11 inches
As you can see this is not easy to do correctly
3 - Measure Time of Flight
By measuring very accurately the Time of Flight between 2 points and we can accurately calculate the BC for that distance. Ideally you calibrate beyond the distance you would shoot at. Two or more distances can be used to create a stepped BC or to be used in ballistic apps that can use this data.
At the same time we capture a highly accurate velocity for each shot
This is done scientifically and accurate to less than 1%.
Every measurement has at least 1 backup reading in it to give comfort in the results
Our system is the only system in the country that can do this.
But I have a Labradar - doesn’t this do it?
In a word NO
The Labradar is capable of measuring the bullets speed to some 50-80m.
Therefore it is only capable of calibrating your BC to that distance - which is ONLY some 10-20% of your actual shooting range or even less !!
It is a great starting point for calculating the BC and good for measuring velocity (remember to set it up correctly) for load development.