Okay, so i have done a bunch of tests with regards to this. Here are my results:
Precision
Range Test: Only using regular arrows here
- 2m - Dont even bother, i never filled up the bar
- 10m - 588 shots
- 20m - 183 shots
- 30m - 130 shots
Target Test: hitting targets with regular arrows
- 20m - 186 shots
Charged Shot Test: charged regular arrows only
- 20m - 40 shots
Piercing Arrow Test: piercing arrows only
- 20m - 74 shots
Rapidity
Range Test: Regular arrows only
- 10m - Did not calculate
- 20m - 201 shots (1.1x more shots than precision)
- 30m - 161 shots (1.2x more shots than precision)
Charged Shot Test: charged regular arrows only
- 20m - 39 shots
Piercing Arrow Test: piercing arrows only
- 20m - 75 shots
Charge Percentages
- Piercing Arrow - 1.33% per arrow
- Charged Shot - 2.56% per arrow
- Regular arrow (precision) - 0.54% per arrow
- Regular arrow (rapidity) - 0.5% per arrow
Conclusions
- Range matters drastically for both rapidity and precision. Going below 20m is not a good idea
- Charged shots and piercing arrows both are better at charging, but they charge the same amount for rapidity and precision
- Hitting targets doesnt increase charge speed at all
- Precision basic arrows charge slightly faster (1.1-1.2x) than rapidity arrows,
- When using the full rotation, rapidity charges only slightly slower than precision on a per arrow basis (1.04x).
- Rapidity would need to shoot only 1.15 shots per second in order to match the charge rate of precision rangers at one per second.
PS
I have the logs for my tests if you want to see them. You can also do the tests yourself 
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