Thanks for posting this thread isoaker. This'll give me the opportunity to think about my own test procedure.
There are two major issues here: 1) optimal firing angle, and 2) how to define range.
In terms of the optimal firing angle, the procedures discussed here are all good, but it becomes very impractical to have to measure 20+ shots for each nozzle. From my understanding, the range changes fairly little within 5 degrees or so of the optimal firing angle. This angle appears to always be below 45 degrees. See the following test results for fire hose nozzles from
this paper:
I'd encourage testing to see if you get similar results for water guns. For the sake of saving time, though, I think it'd be more practical to pick a good angle (say 35 degrees) and do tests at that. Be sure to report the angle so people know what "angled" means.
As for what "range" means, there are many issues. I do agree that the definition has to be practical for water wars. Last drop is not practical at all, as a single drop of water is unlikely to hit your intended target. The last puddle is more clear, though Duxburian brings up a fair point. To me, "last puddle" means "last large puddle". This is still somewhat subjective, but when I did last puddle tests I'd choose the puddle where the majority of the water ended up.
marauder, I think you may have missed isoaker's point. What is the "point of impact"? The stream impacts the ground at multiple points, so it's not clear what the "point of impact" is.
What range means has been an issue in the fire hose nozzle research papers I've read. I've seen two papers use a technique that I believe came from sprinkler testing: the "bucket test". Basically, they set up buckets in a grid at a distance from the fire hose nozzle and measure how much water goes into each bucket (
disposable plastic bowls might be the way to go for this). This way, you know exactly where the water goes and can measure the amount at different spots. This'll give you a great idea of where the water lands, but it also is very tedious. You can turn that into a plot like the following (also from the same paper I mentioned earlier):
I think for my own tests, I might use the bucket method and define the range as the point where 50% of the water is deposited below/above. So, if a water blaster has a lot of spray, it'll be punished for that. Do you all think 50% sounds reasonable? That should be approximately where most of the water goes, which is what we're interested in.
(As a side note, the plot above is for a fire hose nozzle, which tend to have more spray than water blaster nozzles. I suspect that the transition from 100% to 0% is much shorter in water blasters.)