SPRO Cast Control 8X
Diameter chart, reel capacity & backing guide
Cast Control 8X is SPRO's multipurpose casting braid. The chart covers 10-80 lb. Lighter sizes come on 150-meter spools, heavier sizes on 300-meter spools, and some strengths are also offered in 3,000-meter bulk spools.
- Construction
- Japanese eight-strand braid, marketed by SPRO for multipurpose casting
- Listed strengths
- 10-80 lb
- Line type
- Braid main line
Is Cast Control 8X right for your setup?
Cast Control spans lighter spinning-style work through heavier casting setups, but each strength has its own physical diameter. This is particularly important for the unusual 12, 16 and 18 lb steps. Choose the exact package rather than translating those labels to a familiar strength from another braid brand.
How much Cast Control 8X will fit?
Calculated estimates, not measured fills. Stop at the reel manufacturer's fill level even if some line remains.
SPRO Cast Control 8X diameter chart
Only the source-reviewed strengths and package combinations listed below are included. Converted measurements are identified in the source notes.
| Strength | Inches | mm | Spools (m / yd) |
|---|---|---|---|
| 0.005118 | 0.130 | 150 m (about 164 yd) | |
| 0.006299 | 0.160 | 150 m (about 164 yd) | |
| 0.007087 | 0.180 | 150 m (about 164 yd) | |
| 0.007874 | 0.200 | 150 m (about 164 yd) | |
| 0.008661 | 0.220 | 150 m (about 164 yd), 3000 m (about 3280.839895 yd) | |
| 0.009449 | 0.240 | 300 m (about 328 yd), 3000 m (about 3280.839895 yd) | |
| 0.011024 | 0.280 | 300 m (about 328 yd), 3000 m (about 3280.839895 yd) | |
| 0.012402 | 0.315 | 300 m (about 328 yd), 3000 m (about 3280.839895 yd) | |
| 0.01378 | 0.350 | 300 m (about 328 yd), 3000 m (about 3280.839895 yd) | |
| 0.016535 | 0.420 | 300 m (about 328 yd), 3000 m (about 3280.839895 yd) |
Choosing your Cast Control 8X strength
The package image and current web product code identify 16 lb at 0.18 mm. A 2026 catalog row instead says 15 lb. This pack uses the current 16 lb web/package identity and does not rename the existing 16 lb catalog record.
The verified 20 lb filler is 0.22 mm and 150 m; 30 lb is 0.24 mm and 300 m. Both diameter and package length change across that step.
The legacy 22 lb record has no matching current official variant. Newly offered 6 and 8 lb variants lack reviewed diameter labels, so they are not included in this numeric chart.
Specification-based guidance, not a ReelCalc hands-on performance test. Capacity results are estimates, not measured fills.
Want a guided recommendation?
Continue in the Setup WizardSame pound test, different diameters
At your selected strength
Loading diameter comparisons...
What changes with another line?
Nearby diameters in the line database
| Line | Strength | Inches | Difference |
|---|---|---|---|
| Loading line database... | |||
Backing, working line & leaders
Check the strength-to-length pairing
Do not assume the 300 m package is available for every lighter strength. Match the length to the exact product code shown in the evidence.
Bulk is not a separate strength
A 3,000 m bulk package changes purchase quantity, not the selected pound label. Only the explicitly listed bulk strength combinations are included.
Keep the backing join out of casting reach
Select a working length with a reserve before filling unused volume with backing. The 164- or 328-yard label is a purchase limit, not a requirement to fill the reel with the entire package.
How Much Fits on These Reels?
Estimated full-spool capacity for the Cast Control 8X strength selected above, with no backing. These are calculated examples, not physical tests or recommendations for every pairing.
Loading capacity estimates...
Cast Control 8X questions, answered
Is the middle size 15 or 16 lb?
The official 2026 catalog says 15 lb; current web variants and the actual package image say 16 lb. This guide uses 16 lb and flags the catalog disagreement rather than merging both.
Why is 22 lb not shown?
The legacy catalog includes it, but no matching current official product variant or label was verified.
Are the line-size numbers used to calculate diameter?
No. The package labels publish millimeters, which are used directly. The numbered size on the label is not converted into diameter.
How much Cast Control 8X will fit my reel?
Use the exact strength and the reel's published capacity. Pound test is not a fixed diameter, so equal-strength products can produce different fill estimates.
Is one 164-yard package enough?
Only when it covers the planned working length and an appropriate reserve. Backing can fill unused volume, but cannot supply more working line for long casts, deep drops or fish runs.
Specifications & sources
Official sources retrieved September 13, 2026. Millimeter diameters are published; inches are converted by dividing by 25.4. 2026 catalog 15 lb conflicts with current 16 lb product code and package. Current web/package identity used. Legacy 22 lb withheld. New 6/8 lb variants lack verified diameters and are withheld. Meter-only bulk lengths converted at 1 yd = 0.9144 m. Package options are not a stock or price guarantee.
Calculations use the catalog's listed inch diameters. Published inch and millimeter values may differ slightly because of rounding.
- Official SPRO specification source Exact numeric rows, package identity and model positioning.
- Official SPRO specification source Exact numeric rows, package identity and model positioning.