Caliber Pounds as a measure of cannon bore English gun classes c. 1800[ 
 citation needed 
 ]

| gun_class_pdr_ | shot_diameter_cm | shot_volume_cm_3_ | approx_service_bore_cm | mass_of_projectile_kg |
|---|---|---|---|---|
| 2 | 6.04 | 172.76 | 6.64 | 0.90846 |
| 3 | 6.91 | 172.76 | 7.60 | 1.36028 |
| 4 | 7.60 | 230.30 | 8.37 | 1.81339 |
| 6 | 8.71 | 345.39 | 9.58 | 2.71957 |
| 9 | 10.00 | 518.28 | 11.00 | 4.08091 |
| 12 | 10.97 | 691.22 | 12.07 | 5.44269 |
| 18 | 12.56 | 1036.96 | 13.81 | 8.16499 |
| 24 | 13.82 | 1382.65 | 15.20 | 10.88696 |
| 32 | 15.21 | 1843.50 | 16.73 | 14.51572 |
| 64 | 19.17 | 3686.90 | 21.08 | 29.03063 |