| For XI-in., X-in., IX.-in., and 100-Pdr. | For 60, 30, and 20-Pdr. | |
| Inches. | Inches. | |
| Length of bolt under the head | 18. | 14. |
| Diameter of bolt | 4. | 3. |
| Diameter of hole in socket | 4.1 | 3.1 |
| Diameter of hole in boss | 10.5 | 8. |
| Height of boss | 1.5 | 1.1 |
Slot in the pivot-plate, 1/16 larger than the boss.
For XI-in., X-in., IX-in., and 100-pdr. carriages, the fighting and shifting sockets are bossed, the housing-socket plain.
For 60-pdr., 30-pdr., and 20-pdr. carriages, the shifting-socket alone is bossed.
For broadside-guns, the following positions for bolts are established:
| 20 and 24 in. Port-sills. | 16 and 18 in. Port-sills. | |
| Inches. | Inches. | |
| Height of centre of lower bolt from deck | 14.75 | 10.75 |
| Distance between the bolts | 3.75 | 3.75 |
| Distance of centre of 1st bolt from side of port | 14. | 14. |
| Distance of centre of 2d bolt from side of port | 22. | 22. |
| Distance of centre of training-bolt from side of port | 36. | 36. |
| Height of training-bolt from deck | 21. | 14. & 16. |
| Height of securing-bolt (side-tackle bolt) above port-sill | 8. | 8. |
For IX-in. guns, the port-sill should not be less than 20 inches in height, and no port-sill less than 16 inches; otherwise, the carriages will not give sufficient elevation, and the position of the Gun Captain in aiming is exceedingly awkward and inconvenient.
Scraping and staining gun-carriages or keeping them bright is prohibited; they should be kept well painted, and the trucks, axletrees, and trunnion-holes oiled.
All new work shall be primed with red-lead.
Wrought-iron Broadside carriages, for IX-inch, new 8-in. of 6,500 lbs., and 32-pdr. of 4,500 lbs. shell-guns, have been designed by the Ordnance Bureau, submitted to trial with success, and are being issued for service at sea.