One thing that can potentially effect accuracy is the variability of the projectile. I am told that serious hand loaders weigh and sort bullets. For the best accuracy, you want everything the same. This is the only way you can have consistency.
To date, I have taken for granted that all the pellets were the same. On the container, it says that they weigh 7.54 grains. That is a pretty precise measurement. For me to technically validate that, I would need an analytical balance that reads three places past the decimal point such as X.XXX . I am not going to spend $5000 because it is not that important but that is what I would need. I do however have a scale, so I thought that I would give it a shot in just checking what my readings are.
The last digit is considered the degree of certainty. In my scale pictured above, I can only expect numbers ahead of the last digit to be correct. Or said another way, 100.0X can be certain.
When I switch the units from grams to grains, I only get 7.X as precision. This means that the reality is I cannot validate that the pellets are 7.54 grains. The best I can do it get relative comparisons. For fun, I did a couple tests. The first one was to measure one pellet ten consecutive times on slightly different locations on the scale.
| Pellet | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 |
| 1 | 7.8 | 7.6 | 7.7 | 7.8 | 7.7 | 7.8 | 7.7 | 7.7 | 7.7 | 7.8 |
| 2 | 7.6 | 7.6 | 7.6 | 7.6 | 7.6 | 7.6 | 7.6 | 7.6 | 7.6 | 7.6 |
| 3 | 7.7 | 7.7 | 7.7 | 7.6 | 7.7 | 7.6 | 7.6 | 7.7 | 7.7 | 7.7 |
What can we learn from this? Truthfully, not a lot if we know that we can only trust 7.X grains. There is no absolute way to determine the difference between the two pellets. I would say looking at the data, it would appear that consistency improved greatly between measurements for pellet one versus pellet two.
From a relative perspective, it would appear that there is some difference between the pellets. Even though I cannot accurately weigh them, I am getting some different results when I switch pellets and that is consistent. I did a second test to weigh 10 different pellets.
| Pellet | Weight (grains) |
| 1 | 7.9 |
| 2 | 7.6 |
| 3 | 7.7 |
| 4 | 7.9 |
| 5 | 7.9 |
| 6 | 7.6 |
| 7 | 7.9 |
| 8 | 7.9 |
| 9 | 7.7 |
| 10 | 7.8 |
So, it appears that the spread is between 7.6 – 7.9 with a weighting toward the higher end. My conclusion for all of this is I believe that there is some difference with the pellet weight. If I take my measured spread (0.3 grains) and divide by the nominal weight (7.54 grains), I calculate 4%. In reality, that is not a lot but it is something.
End Your Programming Routine: There is some statistical analysis that can be done to determine how accurate your measurements are. Given my equipment’s limitations, I don’t think that it is really worth doing the analysis. This wouldn’t be a question if what I was measuring was heavier. Regardless, I think that this technique has potential to provide context in changes of accuracy.
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