This calculator is meant for standard atmospheric conditions at sea level. This calculator is still untested under real conditions, though it's contrasted with JBM Ballistics.
Compared to JBM Ballistics it's giving comparable results in relation to Drop/Speed/Distance, and it might be even better:
A lot of substeps are taking place (5000 a second)
DOUBLE datatypes are in use
Hermite Interpolation is done to Drag Data
Spindrift is done through a new custom made approximation, and it's not based on a F(Time Of Flight). This might give wrong/different results, but it's good enough, though not all test cases were done during testing.
In case of encountering a problem or for contacting me, go here.