The Data Behind How String Color Can Impact Performance and Precision

After building thousands of strings I know there is variation in the material. But how much variation is there and what do archers need to know about it? I've set a personal record and built 42 strings to find out. I started with a BCY 8125 string of every color I have. They all had the same:

• strand count (16 strands)

• length (65" finished string length)

• end serving (BCY 2X)

• build process

I know there are colors I get a lot of excess wax from as I build and there are colors that give off very little wax. Here's what I found from these 25 colors.

Each color shows the actual excess wax that was stripped off the string as part of the build process. As you can see there are heavily waxed colors, like yellow and white, and those with very little wax like light pink, black, and orange. I wish I could say this is a reliable reference for future strings but unfortunately it is not. Spools of material sometimes come heavily wax and sometimes have very little wax for the next spool of the exact same color. So while this shows great variation, it cannot be considered predictable.

So then I did the whole thing again with the Bloodline Glory Pro material. This material is the same fiber as 8125 (SK75 Dyneema) but in a smaller size. I know it to be more consistent since the material has a proprietary wax-free coating and I've seen less variation between colors. Also practically nothing (or at least nothing measurable) strips off these strings as they are being built. They were built with 26 strands as that creates an equivalent finished outer diameter when compared to the 16 strands of 8125. These also had the same:

• strand count (26 strands)

• length (65" finished string length)

• end serving (BCY .008 Spectra)

• build process

Finished string stats

Outer diameter

So how did they stack up in terms of string size? Each string was measured with micrometers after it was built (but before pre-stretching) under 200 lbs of tension in 5 different places on the string and averaged. The charts below show each color and it's finished outer diameter.

The scales for each chart are the same, ranging from 66-90 thousandths of an inch so we can compare the variability of the 2 materials. The average value is marked by a dotted line on each graph.

Weight

A thicker string should weigh more. So how did these string colors and materials compare when it comes to mass weight of the string?

Again, the scales for each chart are the same, ranging from 70-110 grains so we can compare the variability of the 2 materials. The average value is marked by a dotted line on each graph.

Analysis

Discrepancies

While there are trends here that align between the weight and diameter information, some do not.

• Flo orange 8125 - this has a large outer diameter (12% over average) and also the heaviest weight (24% over average) of the 8125 strings. That material is pretty chunky, so that's no surprise. What is a surprise is how little wax stripped off in the build process for this color.

• Flo green Glory Pro was a wider finished string (6% over average), but not drastically so and it ended up being significantly heavier (22% over average) than the other Glory Pro colors.

• White 8125 - in the first chart showing the excess wax stripped off while building the string, white was pretty high up there producing the 3rd most wax of all the string colors. Yet the outer diameter of the finished strings was just below average and the weight of that finished string was even further below average.

Consistency

I may not be able to explain why these discrepancies exist, but we can look at what is the most consistent in all this data.

The spread of finished weights across all the colors seems to be about the same for both the 8125 and Glory Pro. Where we do see a significant difference is in the range of outer diameters between the two materials. The 8125 strings ranged form .070" to .087", giving us a .017" range. The Glory Pro material ranged from .072" to .082", giving us a much smaller .010" range. This can be further visualized in the radial diagram where the red area shows the size (outer diameter in thousandths of an inch) per color of 8125 and the purple area shows that of the Glory Pro. The smaller purple area shows more consistency in the outer diameter across the selection of colors.

String mass weight take-aways

So what can we learn from all this? Well first let's look at the mass weight variations. Some colors are far heavier than other colors. And this change in weight can affect your tune.

• Lighter strings* will put more energy into the arrow, increasing its speed and thus causing the arrow to fly weaker.

• Heavier strings* will put less energy into the arrow, reducing the arrow speed and causing it to fly stiffer.

*Can be achieved by adjusting strand count, color, material, or a combination of these.

I was recently helping an archer tune two bows that had a two pound difference in draw weight. Since we wanted to tune both bows to the same set of arrows and the limb bolts were bottomed out on the lighter limbs, we had very few variables to work with to tune. We ended up putting a heavier string (118.1 gn) on the bow with the higher draw weight and a lighter string (98.5 gn) on the lighter bow to get them both to tune with the same arrows.

This can be used to your advantage to help tune, but at the very least you should be aware that this can have an affect on your tune and you should proceed with caution when switching string colors.

String size take-aways

The finished outer diameter of your string can affect which nocks will fit that string. While we can use different size serving material for the center serving, there's only so much that can do.

Example: Let's say you are shooting an 18 strand 8125 string and you are using Easton small groove pin nocks. Your current string is red and is an outer diameter of about .070". With the thinnest viable center serving that's about as tight as you want that nock to be. So then you decide for your next string you want the brighter flo red. That same material and strand count will now be about .087" and there's no way those nocks will still fit with the string that much wider plus center serving.

So what does this mean for you?

1. Just knowing that there could be thickness differences between colors will help make more informed color choices. Switching colors between seasons when you are resetting your bow anyway may be a good way to go if you are considering a color change.

2. Going with a more consistently-sized material like Glory Pro can help minimize size changes between colors.

3. If you are switching to a thicker color, you may need to switch nocks to accommodate the added thickness. Likewise if you are switching to a thinner color, smaller nocks may be preferable to get a good nock fit. See the nock guide for complete nock size information.

4. For those who prefer a multi-colored string, those colors are not necessarily equal as some strands could be colors that are bigger than others. This can build inconsistency into your string and the strands won't all necessarily be handling the load evenly. While I won't go as far as to say archers should not use multi-colored strings, I will say those elite archers who value performance over all else may want to keep this in mind. I don't recall seeing any multicolored strings in the top 16 for the last Olympic games.

Summary

After building and testing 42 strings across two materials and 25+ colors, it’s clear that string color isn’t just an aesthetic choice—it can directly impact both performance and precision. Waxed materials like 8125 show significant variation in size and weight across colors, while Glory Pro offers much more consistency thanks to its wax-free coating.

These differences in string diameter and mass weight can affect arrow speed, nock fit, and ultimately your tuning. Whether you're chasing peak performance or looking for a color refresh, understanding how string color influences these factors will help you make smarter choices. And if precision matters most, a consistent material and single-color string might just give you the edge.