picture of this weapon?
These were 4"/27 (10.2 cm) guns converted to take the same cartridge case ammunition as used for the 4"/40 (10.2 cm) QF guns. Between 20 and 27 guns were converted from 4"/27 (10.2 cm) BL Marks IIIA, IV, V and VI. These were redesignated as QFC I/IIIA, QFC I/IV, QFC I/V and QFC I/VI, although in gun lists they were always referred to only as 4" (10.2 cm) QFC guns. Actual bore length as converted was 27.78 calibers.
These guns were converted by giving them either new 'A' tubes or short bore and chamber liners, which resulted in them having the same chamber size as the 4"/40 (10.2 cm) QF guns. These converted QF guns replaced BL guns on Inflexible and the gunboat Lapwing. During World War I, a few were still in service on DAMS and three were used by Belgian gunboats on Lake Tanganyika in Africa.
| Designation | 4"/28 (10.2 cm) QFC Marks I/IIIA, I/IV, I/V and I/VI |
|---|---|
| Ship Class Used On | Inflexible, Lapwing and DAMS |
| Date Of Design | as QFC: About 1895 |
| Date In Service | as QFC: 1895 |
| Gun Weight | 2,912 lbs. (1,321 kg) |
| Gun Length oa | 120 in (3.048 m) |
| Bore Length | 111.1 in (2.822 m) |
| Rifling Length | N/A |
| Grooves | N/A (probably 24) |
| Lands | N/A |
| Twist | N/A |
| Chamber Volume | 213 in3 (3.49 dm3) |
| Rate Of Fire | about 8 - 10 rounds per minute |
| Type | Separate |
|---|---|
| Projectile Types and Weights | HE: 25 lbs. (11.3 kg) |
| Bursting Charge | N/A |
| Projectile Length | N/A |
| Propellant Charge | 3.56 lbs. (1.6 kg) Cord 15 |
| Muzzle Velocity | 2,192 fps (668 mps) |
| Working Pressure | N/A |
| Approximate Barrel Life | N/A |
| Ammunition stowage per gun | N/A |
| Elevation | Distance |
|---|---|
| World War I Range @ 20 degrees | 9,000 yards (8,230 m) |
Data from:
- "British Naval Guns 1880-1945 No 17" article by John Campbell in "Warship Volume X"