According to Ian Hogg's books on artillery, the following lengths of the gun apply:
13.5" gun: 625.9 inches, bore 45 calibers
14" gun: 648.4 inches, bore 45 calibers
18" howitzer: 648.4 inches, bore 35 calibers
The lengths of the 14 and 18 in pieces are identical - no surprise, both were manufactured by Elswick and were intended to be interchangeable on the same carriage.
The 13.5 and 14 in guns both have a caliber length of 45 - also no surprise, as both were designed as battleship main guns, the 14 in gun slightly later (and larger) than the 13.5 in gun.
Now, the difference in gun length between the 13.5" gun mounted in GLADIATOR WW2 and the 14" gun mounted in BOCHE BUSTER WW1 is 22.5 inches, this amounts to 7.5 mm in 00 scale (1/76.2).
Judging from photos, the barrel lengths (muzzle position relative to the buffers) seem identical to me (which they should not be). Does anybody have both models available for a direct comparison?
Next, gun caliber. My BOCHE BUSTER model (OR76BOOM01) has a muzzle opening clearly exceeding 6 mm (6 mm is the scale caliber of an 18" howitzer). The muzzle should be 4.67 mm to match a 14" gun (and 4.5 mm to match a 13.5" gun).
These observations lead me to ask the question: Do we in fact have the same model of the 18" howitzer dressed up as either a 14" gun (BOCHE BUSTER WW1) or a 13.5" gun (GLADIATOR WW2)?
