ISO dimension series 03 · deep groove ball bearings
6300 series bearing dimensions
ISO dimension series 03 deep groove ball bearings, commonly called the medium series.
This table covers 11 basic designations from 6300 to 6310, with bores from 10 to 50 mm. “medium series” is the informal trade description; ISO identifies the range by dimension series 03.
| Designation | Bore d | Outside D | Width B |
|---|---|---|---|
| 6300 | 10 mm | 35 mm | 11 mm |
| 6301 | 12 mm | 37 mm | 12 mm |
| 6302 | 15 mm | 42 mm | 13 mm |
| 6303 | 17 mm | 47 mm | 14 mm |
| 6304 | 20 mm | 52 mm | 15 mm |
| 6305 | 25 mm | 62 mm | 17 mm |
| 6306 | 30 mm | 72 mm | 19 mm |
| 6307 | 35 mm | 80 mm | 21 mm |
| 6308 | 40 mm | 90 mm | 23 mm |
| 6309 | 45 mm | 100 mm | 25 mm |
| 6310 | 50 mm | 110 mm | 27 mm |
What dimension series 03 means
Dimension series 03 combines width series 0 with diameter series 3. Bearings can share a bore while having a different outside diameter and width. The shaft, housing bore and available axial space must therefore match all three dimensions; choosing a larger series is not a drop-in upgrade.
Load ratings and limiting speeds are not published here because they depend on the exact manufacturer and variant. Use the maker's current datasheet for engineering selection.