Japanese Black Bolt Pack Weight Test | 20 Packs Measured for SAR, AR, RR & Mirror Cards
In my first English pack-weight test, I measured all 30 packs from a Japanese The Glory of Team Rocket booster box and compared the results after opening every pack.
This time, I tested Black Bolt.
For this experiment, I used 20 seven-card packs from an unopened Japanese Black Bolt booster box that I purchased myself.
I weighed every sealed pack individually to the nearest 0.01g, then opened all 20 packs and recorded the relationship between pack weight, card rarity, and special Mirror Holofoil cards.
Black Bolt is particularly interesting for this type of test because, in addition to its seven-card pack format, it includes both Poké Ball Mirror and Master Ball Mirror cards.
The overall result was clear.
In this booster box, the SAR and some RR cards appeared in relatively heavier packs.
However, AR, R, and Poké Ball Mirror cards overlapped within similar weight ranges, while the Master Ball Mirror card appeared in the lightest pack of the entire test.
Therefore:
Pack weight alone could not reliably identify card rarity or the presence of a Mirror Holofoil card.
This article documents an experiment into whether what is commonly known as “pack weighing” can actually distinguish the contents of unopened booster packs.
It is not intended to encourage weighing packs in stores, selecting packs by weight before purchase, or selling packs that have been sorted by weight.
Pack weight may be affected by packaging material, printing, card finishes, Mirror Holofoil treatments, manufacturing variation, and the measuring environment.
The measurements shown here are results from this specific booster box and these 20 packs.
They should not be treated as universal standards for other booster boxes, production batches, or loose packs.
Test Conditions
The test was conducted under the following conditions.
- Product: Japanese Black Bolt expansion
- Purchase format: unopened booster box
- Number of packs measured: 20
- Cards per pack: 7
- Every pack was weighed while sealed
- Measurement precision: 0.01g
- Location: normal indoor environment
- All packs were opened after weighing
- Card rarity and Mirror Holofoil type were recorded
Japanese Black Bolt includes Poké Ball Mirror and Master Ball Mirror cards in addition to standard cards and higher-rarity cards.
This means that differences in pack weight may not be caused only by rarities such as SAR or RR.
The wrapper, printing coverage, surface treatment, Mirror Holofoil card, and other manufacturing differences may all affect the final measurement.
For this reason, the measurements below should not be treated as absolute thresholds.
They are real measurements used to compare 20 packs relative to one another within the same booster box.
Black Bolt Pack Weight Results: 20 Packs Measured
The 20 packs measured in this test ranged from:
Measured range: 11.71g–11.83g
Difference between lightest and heaviest pack: 0.12g
This booster box produced SAR, AR, and RR cards as well as Poké Ball Mirror and Master Ball Mirror cards.
Some relatively heavy packs contained the SAR or RR cards.
However, not every high-rarity or special card appeared in a heavy pack.
Most notably, the Master Ball Mirror card appeared in the lightest pack of the entire test at 11.71g.
Overall, different rarities and Mirror Holofoil cards overlapped substantially across similar weight ranges.
What the Measurements Showed
The main findings from these 20 packs were:
- The overall pack-weight range was 11.71g–11.83g
- The Master Ball Mirror appeared at 11.71g
- Poké Ball Mirror cards appeared from 11.73g to 11.83g
- The SAR appeared at 11.81g
- RR cards were mainly found between 11.76g and 11.83g
- AR cards appeared between 11.73g and 11.79g
- Multiple rarities and Mirror Holofoil cards overlapped within similar weight ranges
In this booster box, the SAR and some RR cards were found toward the heavier end of the range.
However, AR cards appeared within weight ranges similar to R cards, and the Master Ball Mirror appeared in the lightest pack.
This shows that card rarity or the presence of special foil treatment does not translate directly into a heavier overall booster pack.
Master Ball Mirror Pack Weight
The Master Ball Mirror card found in this test came from a pack weighing 11.71g.
This was the lightest of all 20 packs measured.
A Master Ball Mirror has a distinctive special foil treatment, but the result from this box shows that the presence of such a card does not necessarily make the overall pack heavier.
The only conclusion that can be drawn from this measurement is:
In this booster box, the Master Ball Mirror was found in an 11.71g pack.
It does not mean that lighter packs are more likely to contain Master Ball Mirror cards or that Master Ball Mirror packs are generally lighter.
Only one Master Ball Mirror was observed in this test.
More booster boxes would need to be measured before any repeatable pattern could be evaluated.
Poké Ball Mirror Pack Weight
Poké Ball Mirror cards appeared in packs weighing between 11.73g and 11.83g.
This is a very wide range covering both relatively light and relatively heavy packs.
No narrow weight range unique to Poké Ball Mirror cards was observed.
Because Poké Ball Mirror cards appear more frequently than Master Ball Mirror cards, they may contribute to differences in total pack weight.
However, many other factors can also affect the final measurement, including regular cards, higher-rarity cards, and the wrapper itself.
As a result, the presence of a Poké Ball Mirror card could not be determined from pack weight alone.
SAR Pack Weight
The SAR found in this booster box came from a pack weighing 11.81g.
This was toward the heavier end of the 20-pack weight distribution.
It is possible that the card's surface treatment or the overall combination of cards in the pack contributed to its higher weight.
However, other rarities and Mirror Holofoil cards also appeared around the same weight range.
Only one SAR was observed in this test.
Therefore, the only conclusion supported by the data is:
In this booster box, the SAR was found in a relatively heavy 11.81g pack.
This does not mean that packs around 11.81g contain an SAR or that the heaviest packs can reliably be identified as SAR packs.
RR Pack Weight
RR cards were mainly found between 11.76g and 11.83g.
Many of them appeared toward the heavier end of the overall distribution.
This could indicate that RR cards contributed slightly to the total pack weight in this particular booster box.
However, the same weight range also included SAR, AR, R, and Mirror Holofoil results.
A heavier pack therefore did not necessarily indicate the presence of an RR card.
Other factors, including Poké Ball Mirror cards and differences in the packaging, may also have contributed to the measurements.
No weight range unique to RR packs was identified.
AR Pack Weight
AR cards were found between 11.73g and 11.79g.
They appeared from the lighter side of the distribution through the middle of the overall range.
Their measured weights also overlapped with R cards and Poké Ball Mirror packs.
Even if the special surface treatment of an AR card adds some weight, that difference may be small enough to overlap with variations in the other cards or the wrapper.
No clear boundary was found that could separate AR packs from the other packs.
Therefore, AR cards could not be identified reliably using pack weight alone.
How Mirror Holofoil Cards Affect Pack Weight
Japanese Black Bolt contains both Poké Ball Mirror and Master Ball Mirror cards.
It is reasonable to consider whether their additional surface treatment could affect the total weight of a sealed pack.
However, the results from this booster box did not show either Mirror Holofoil type clustering within one specific weight range.
The Master Ball Mirror appeared in the lightest pack.
Poké Ball Mirror cards appeared across a broad range extending from relatively light packs to some of the heaviest packs.
This suggests that Mirror Holofoil treatment alone does not determine the total weight of a booster pack.
The combination of cards, printing and cutting variations, packaging material, and other factors likely contribute to the final measurement.
Results by Weight Range
The results from this booster box can also be grouped into three approximate weight ranges.
✅11.71g–11.75g: AR, R, and Mirror Holofoil results overlapped
The lightest pack in the entire test, weighing 11.71g, contained the Master Ball Mirror.
AR and Poké Ball Mirror cards also appeared among relatively light packs.
This means that a light pack was not necessarily a standard or low-rarity-only pack.
✅11.76g–11.79g: RR, AR, R, and Mirror Holofoil results overlapped
Several different rarity and Mirror Holofoil results appeared in this range.
RR and AR cards were both found here, but there was no clear weight boundary separating them.
✅11.80g–11.83g: SAR and RR cards appeared
The SAR in this test appeared at 11.81g, while some heavier RR packs reached 11.83g.
Higher-rarity cards were found in this heavier range.
However, other types of packs also appeared nearby, so this was not a range where a high-rarity card could be considered guaranteed.
Can Japanese Black Bolt Packs Be Weighed to Identify Rarity?
In this booster box, the SAR and some RR cards appeared in relatively heavy packs.
However, several other results make pack weight unreliable as a method of identifying the contents.
- The Master Ball Mirror appeared in the lightest pack of the test
- AR cards overlapped heavily with R cards
- Poké Ball Mirror cards appeared across a wide weight range
- Multiple rarities and Mirror Holofoil cards shared similar weights
- Packaging and manufacturing variation can also affect total pack weight
Based on these results, there were some weight tendencies within this booster box, but pack weight alone could not accurately identify SAR, AR, RR, Poké Ball Mirror, or Master Ball Mirror packs.
The measurements in this article should be viewed as data from a fully opened booster box, not as weight thresholds for selecting packs.
Summary of the Black Bolt Pack Weight Test
The 20 Japanese Black Bolt packs measured in this test ranged from 11.71g to 11.83g.
The main results were:
- Master Ball Mirror: 11.71g
- Poké Ball Mirror: 11.73g–11.83g
- SAR: 11.81g
- RR: mainly 11.76g–11.83g
- AR: 11.73g–11.79g
- Multiple rarities and Mirror Holofoil cards overlapped within similar weight ranges
- Pack weight alone could not accurately identify the contents
The SAR and several RR cards were found in relatively heavy packs.
However, the Master Ball Mirror appeared in the lightest pack, while AR and Poké Ball Mirror cards were distributed across broader weight ranges.
For this reason, the results from Japanese Black Bolt do not support the idea that heavier packs automatically contain higher-rarity cards.
This is the second pack-weight dataset published on the English version of tekemero.com.
The next test will focus on White Flare, another seven-card Japanese booster product that also includes Poké Ball Mirror and Master Ball Mirror cards.
That should make it possible to compare the two products under very similar testing conditions.
