An even older turret ship: the GB/BB/1868

I thought that the next step could be an even older turret ship, a contemporary to the Monarch and Captain: the GB/BB/1868. There is the minor detail that I didn't try to deal with masts and rigging. Unless such a feature were added to Springsharp, to be able to handle rigged ships, I wouldn't even attempt such a thing. This ship has 4-12 guns and 6-4in guns. The armour basis is 12in and the deck is 3in. The belt is complete, although the ends are thinner. The speed is low: just 12 knots. This is the Springsharp report:

GB/BB/1868 turret ship, Great Britain Battleship laid down 1868
Central citadel ship

Displacement:
 9,298 t light; 9,649 t standard; 10,570 t normal; 11,307 t full load

Dimensions: Length (overall / waterline) x beam x draught (normal/deep)
 (339.00 ft / 325.00 ft) x 68.00 ft x (27.00 / 28.60 ft)
 (103.33 m / 99.06 m) x 20.73 m  x (8.23 / 8.72 m)

Armament:
      4 - 12.00" / 305 mm 25.0 cal guns - 642.00lbs / 291.21kg shells, 90 per gun
   Breech loading guns in Coles/Ericsson turret mounts, 1868 Model
   1 x Twin mount on centreline, forward evenly spread
   1 x Twin mount on centreline, aft deck centre
      6 - 4.00" / 102 mm 25.0 cal guns - 23.79lbs / 10.79kg shells, 150 per gun
   Breech loading guns in casemate mounts, 1868 Model
   6 x Single mounts on sides amidships
      Weight of broadside 2,711 lbs / 1,230 kg

Armour:
   - Belts:  Width (max) Length (avg)  Height (avg)
 Main: 12.0" / 305 mm 240.00 ft / 73.15 m 16.00 ft / 4.88 m
 Ends: 8.00" / 203 mm   85.00 ft / 25.91 m 16.00 ft / 4.88 m
   Main Belt covers 114 % of normal length

   - Torpedo Bulkhead:
  1.00" / 25 mm 240.00 ft / 73.15 m 27.00 ft / 8.23 m

   - Gun armour: Face (max) Other gunhouse (avg) Barbette/hoist (max)
 Main: 12.0" / 305 mm 8.00" / 203 mm        -
 2nd: 8.00" / 203 mm 5.00" / 127 mm  8.00" / 203 mm

   - Armoured deck - multiple decks: 3.00" / 76 mm For and Aft decks
 Forecastle: 3.00" / 76 mm  Quarter deck: 3.00" / 76 mm

   - Conning towers: Forward 12.00" / 305 mm,  Aft 0.00" / 0 mm

Machinery:
 Coal fired boilers, simple reciprocating steam engines, 
 Direct drive, 1 shaft, 4,411 ihp / 3,290 Kw = 13.00 kts
 Range 4,200nm at 8.00 kts
 Bunker at max displacement = 1,657 tons (100% coal)

Complement:
 520 - 677

Cost:
 £0.621 million / $2.483 million

Distribution of weights at normal displacement:
 Armament: 266 tons, 2.5 %
 Armour: 4,179 tons, 39.5 %
    - Belts: 2,444 tons, 23.1 %
    - Torpedo bulkhead: 240 tons, 2.3 %
    - Armament: 468 tons, 4.4 %
    - Armour Deck: 903 tons, 8.5 %
    - Conning Tower: 125 tons, 1.2 %
 Machinery: 1,130 tons, 10.7 %
 Hull, fittings & equipment: 3,723 tons, 35.2 %
 Fuel, ammunition & stores: 1,272 tons, 12.0 %
 Miscellaneous weights: 0 tons, 0.0 %

Overall survivability and seakeeping ability:
 Survivability (Non-critical penetrating hits needed to sink ship):
   14,603 lbs / 6,624 Kg = 25.2 x 12.0 " / 305 mm shells or 2.8 torpedoes
 Stability (Unstable if below 1.00): 1.40
 Metacentric height 5.0 ft / 1.5 m
 Roll period: 12.7 seconds
 Steadiness - As gun platform (Average = 50 %): 95 %
   - Recoil effect (Restricted arc if above 1.00): 0.36
 Seaboat quality  (Average = 1.00): 1.89

Hull form characteristics:
 Hull has raised forecastle, rise aft of midbreak, low quarterdeck ,
   a ram bow and a cruiser stern
 Block coefficient (normal/deep): 0.620 / 0.626
 Length to Beam Ratio: 4.78 : 1
 'Natural speed' for length: 18.03 kts
 Power going to wave formation at top speed: 39 %
 Trim (Max stability = 0, Max steadiness = 100): 50
 Bow angle (Positive = bow angles forward): -3.00 degrees
 Stern overhang: 5.00 ft / 1.52 m
 Freeboard (% = length of deck as a percentage of waterline length):
    Fore end,  Aft end
    - Forecastle: 15.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Forward deck: 20.00 %,  11.00 ft / 3.35 m,  11.00 ft / 3.35 m
    - Aft deck: 28.00 %,  19.00 ft / 5.79 m,  19.00 ft / 5.79 m
    - Quarter deck: 37.00 %,  11.00 ft / 3.35 m,  11.00 ft / 3.35 m
    - Average freeboard:  14.44 ft / 4.40 m
 Ship tends to be wet forward

Ship space, strength and comments:
 Space - Hull below water (magazines/engines, low = better): 68.2 %
  - Above water (accommodation/working, high = better): 92.7 %
 Waterplane Area: 16,161 Square feet or 1,501 Square metres
 Displacement factor (Displacement / loading): 136 %
 Structure weight / hull surface area: 158 lbs/sq ft or 772 Kg/sq metre
 Hull strength (Relative):
  - Cross-sectional: 0.88
  - Longitudinal: 2.90
  - Overall: 1.00
 Hull space for machinery, storage, compartmentation is excellent
 Room for accommodation and workspaces is adequate
 Ship has slow, easy roll, a good, steady gun platform
 Excellent seaboat, comfortable, can fire her guns in the heaviest weather