On a Georgian frigate, the lower deck was called the gun deck but had no guns (Millar 10). But that did help ensure that the upper deck was safely above the water.
For the British navy, there was no systematic distribution of the different gun sizes among ships of different classes, and among the different decks of a given ship, until 1677, when it adopted a "solemn, universal, and unalterable adjustment of the gunning and manning of the whole fleet." (Tanner 233ff). This was altered (snicker) by the "establishments" of 1691, 1706, 1719, and 1745. After that warship design became somewhat more diverse again.
Gun Weight
After armor was introduced in the nineteenth century, warship design became "weight critical"-the hull displacement provided a particular amount of buoyancy, and the ship couldn't be heavier, so designers had to make compromises vis-a-vis weight of guns, engines, armor, and even fuel and ammunition carried.
As a loose rule of thumb, gun weight is proportional to the cube of the caliber (Meigs 204) and thus, for roundshot, proportional to the shot weight. For early-nineteenth-century British iron guns, gun weight was 170–411 times the latter. (Beauchant 102). Big guns have greater range, but small guns have a higher rate of fire.
We have already alluded to the fact that bronze guns could be made lighter than cast iron ones of the same caliber; steel guns had a similar advantage over their predecessors, because of steel's greater tensile strength per unit weight.
Guns designed to only fire shells (hollow projectiles) could be lighter than those firing solid shot; shells were lighter than solid shot of the same caliber; hence less powder was needed to project them; hence the gun barrels could be thinner. Or, keeping gun weight the same, you could increase caliber. The Paixhans 80-pounder shell gun (1837) weighed the same as the traditional 36-pounder. (Tucker 1320).
Gun Crew
There's some data on crew size in Table 2A. In early nineteenth century French naval service, 14 men attended a 36-pounder; 12, a 24-pounder, 10, an 18- or 12- pounder, 8, an 8-pounder; and 6, a 6- or 4-pounder. (Douglas 149). A carronade only needed 4 men. (163).
Miller (57) provides the rule of thumb that one man was required for every 5 cwt. (112 pounds) of gun weight, although I think that's on the low side. However, he makes the point that gun crews changed constantly; if only one side were engaged, the free crews would come over to help; but crewmen would also be pulled off to handle the ship or to form a boarding party.
Gun Loading; Rate of Fire
It's dangerous to assume that the rate of fire was as good in the 1630s as in the more familiar Napoleonic period (Hornblower Syndrome!).
A modern crew of four handling a replica sixteenth-century wrought iron breechloader required 5 -10 minutes per shot (Konstam 40). An experienced crew might well do better, but on the other hand, handling a large muzzleloader would be more time-consuming. Elizabethan sea dogs probably just fired one broadside at point-blank range and then fought a boarding action. (Konstam 40).
"In 1646 Master gunner William Eldred stated, in The Gunner's Glasse that a maximum of ten rounds an hour could be fired from a gun, and that after forty shots had been fired an interval of an hour must be allowed to cool the piece." (Hughes 35).
The fastest fixed guns on a seventeenth- (or eighteenth-)century warship were the swivel guns. There were breechloaders with removable chambers, and by having several prepped chambers handy, one could get off several shots quickly-perhaps one a minute, at least until the preps were used up. (Konstam 40). They were short range weapons, intended for anti-personnel use, and I imagine that sustained rapid fire wasn't necessary; either the enemy boarding action was fended off, or it wasn't.
Shells cannot be fired as fast as shot because the fuses have to be prepared and adjusted; percussion fuses are less trouble than time fuses. (Owen 338).
For eighteenth-century field artillery (3 -12 pounders), a good rate of fire for an eight-man crew was considered to be two aimed shots per minute (Peterson 119), and this could be doubled by eliminating steps (such as sponging the bore). dangerous, but not as much getting overrun by the enemy. Speed was affected by the weight of the piece; a 12-pounder might only get off one round a minute. (Wise 31).
The rate of fire at sea was lower. (Smaller gun crews? Ship movement?) In 1738, the 70-gun Hampton Court "fire 400 rounds in twenty-five minutes which suggests that each gun fired about one round every two minutes." (Rodger 540). The USS Constitution could fire its 24-pounders, which had a twelve-man crew, one round every three minutes. (Mehl 33).
Other published estimates include one round every 3–5 minutes for the early modern era (Volo 256); three broadsides in five minutes (Hill 55); at best one round a minute for the Napoleonic British navy (Miller 58); for best crews under perfect conditions, one round every four or five minutes in 1660 and one a minute in 1756 (Ireland 48).
Gunlocks improved rate of fire; Collingwood's flagship Dreadnought "could fire her first three broadsides in three and a half minutes." (Rodger 540). Such a firing rate could not be sustained; the gunners would tire; there would be casualties; smoke would slow down the aiming process.
Note that the British and American crews of the Napoleonic period typically got off 1.5–3 times as many shots as a French or Spanish opponent. (Toll 7). The 74-gun Guerriere at Minorca (1756) fired 659 rounds in 3.5 hours (5.5 rounds/hour), and another French ship averaged 6 rounds/hour at the Saintes; either the crews were less handy or the French were deliberately taking their time. (Rodger 540).
The heavy rifled breechloaders of HMS Warrior (1861) were a bit faster than the old smoothbore carriage guns, firing perhaps once a minute. On the other hand, the rifled muzzle loaders were very slow. To reload, the barrels had to be fully depressed and sometimes they had to be traversed to the fore or aft position, too. That gave them a rate of fire of just one shot every three minutes. When breechloaders were reintroduced, those with the full screw closure only improved the situation a little, to once every two minutes. (Hill 55).
The elevating screw increases accuracy but not necessarily speed. In tests at Shoeburyness, a 40-pdr rifled breechloader fired 10 rounds in 7.5 minutes using the screw, and in just 6 minutes with the wedge. (Owen 337).
In the ACW, the big guns were slow. With the 15-inch Dahlgren, the average time between shots was 6 minutes; depending on conditions, it might take 3 -10 minutes to fire again. On the other hand, a long 32-pdr or 9-inch shell gun might be fired once every forty seconds. (Canfield).
Late-nineteenth-century breechloading deck guns, with pivot mounts, appeared to have firing rates of 10 rounds/minute. (Mehl 81, 85).
Even with the same model of gun, rates of fire will differ from ship to ship. In 1902, with the Mark VII 6-inch quick-fire, nine British warships exhibited prize firing rates that ranged from 4.17-7.38 rounds/minute. With heavier guns the range was 0.62 -1.25. (Brassey 38).