wolfmangreg
HAM Ranger
Last edited:
Have gone full stop, Coke bottle glasses, pocket protector wearing nerd since getting the Athlon Rangecraft chrony.
Recently re-tuned my Taipan Veteran II. Out of the box, it was much too hot with middleweight pellets, so had turned the hammer spring way down. That change alone brought excellent accuracy, while still showing decent extreme spread & standard deviation numbers. It was competition season, so left it in that state of tune. With winter here, decided to move the regulator setting a bit lower & adjust hammer spring until a 2-3% under plateau. While I didn't end up at the same average velocity, the changes were successful- accuracy is as good or slightly better than before, while ES & SD improved.
With the Vet II tuned up & new chronograph at my disposal, it was time to nerd out. See a metric crap ton of data sets in my new(ish)role at work, & was quickly reminded of an inescapable truth from Statistics 101- sample size matters. 5-shot groups or 10-shot chrony strings aren't useless; they can give you a quick snapshot of what's going on, and can definitely tell you what does NOT work when ammo or tune testing. But they are prone to false positive results at times. Think we all have fond memories of a magic, 0.4 MOA, 5-shot 100-yard group we shot one time- a result we cannot replicate, or maybe even approach, on a regular basis. I'm guilty.
That said, I'm trending toward a longer term, higher data point count approach to assessing the performance of a particular rig.
The numbers in this table are the combined results of four shooting sessions- one 50 shots, three 40 shots for 170 total data points. Environmental conditions were close enough between the four sessions as to keep any effects negligible. Bottle pressure during all four sessions was somewhere in the 150-240 bar range.
Openly admit to not knowing precisely how these numbers reflect performance on target. For example, no idea how much inherent vertical dispersion to expect with a 30 fps extreme spread at 75 yards, etc. In my particular airgun usage scenarios, can probably get away with much bigger spreads than we airgun nerds like to see. My skill (or lack thereof) is going to the ultimate limiting factor. But tighter spreads & smaller deviations have to help at some level, and can't hurt, so I still see validity in their pursuit. Can't pin a number on how much a shooter's confidence in their equipment translates to success on target, but darn sure believe it has an influence.
The numbers in that table definitely give me confidence in this rifle, so here be a happy wolfman.
Just for giggles - and to completely contradict my yapping about the virtues of large sample size
- some more data tidbits:
Recently re-tuned my Taipan Veteran II. Out of the box, it was much too hot with middleweight pellets, so had turned the hammer spring way down. That change alone brought excellent accuracy, while still showing decent extreme spread & standard deviation numbers. It was competition season, so left it in that state of tune. With winter here, decided to move the regulator setting a bit lower & adjust hammer spring until a 2-3% under plateau. While I didn't end up at the same average velocity, the changes were successful- accuracy is as good or slightly better than before, while ES & SD improved.
With the Vet II tuned up & new chronograph at my disposal, it was time to nerd out. See a metric crap ton of data sets in my new(ish)role at work, & was quickly reminded of an inescapable truth from Statistics 101- sample size matters. 5-shot groups or 10-shot chrony strings aren't useless; they can give you a quick snapshot of what's going on, and can definitely tell you what does NOT work when ammo or tune testing. But they are prone to false positive results at times. Think we all have fond memories of a magic, 0.4 MOA, 5-shot 100-yard group we shot one time- a result we cannot replicate, or maybe even approach, on a regular basis. I'm guilty.
That said, I'm trending toward a longer term, higher data point count approach to assessing the performance of a particular rig.
The numbers in this table are the combined results of four shooting sessions- one 50 shots, three 40 shots for 170 total data points. Environmental conditions were close enough between the four sessions as to keep any effects negligible. Bottle pressure during all four sessions was somewhere in the 150-240 bar range.
| Average | 924.2 |
| Min | 918.0 |
| Max | 931.4 |
| SD | 2.8 |
| ES | 13.4 |
Openly admit to not knowing precisely how these numbers reflect performance on target. For example, no idea how much inherent vertical dispersion to expect with a 30 fps extreme spread at 75 yards, etc. In my particular airgun usage scenarios, can probably get away with much bigger spreads than we airgun nerds like to see. My skill (or lack thereof) is going to the ultimate limiting factor. But tighter spreads & smaller deviations have to help at some level, and can't hurt, so I still see validity in their pursuit. Can't pin a number on how much a shooter's confidence in their equipment translates to success on target, but darn sure believe it has an influence.
The numbers in that table definitely give me confidence in this rifle, so here be a happy wolfman.
Just for giggles - and to completely contradict my yapping about the virtues of large sample size
- some more data tidbits:- First, cold bore shots (rifle unfired for at least 24 hours in every case) measured 927.8, 919.6, 923.2, & 926.2 fps.
- Two of those four shots were also from a freshly cleaned barrel; 923.2 & 926.2 fps.
