Quote Originally Posted by Oleander Ardens View Post
I have a question: How did the range and momentum of the 32 and 36-pounders stand up to the 24 pounders?
When it comes to actual values for penetrating wood I have found various values which overall is 50/50 confusing and enlightening. Some suggest a linear increase from velocity and others closer to the square of velocity. If penetrating wood resembles the physics behind steel plate then one solid oak plank of say 12 inches is stronger than 2 planks of 6 inches each. That might have something to do with the different test numbers I have seen.

Apparently some US test from the IIRC 1820's showed that a 24 pounder could penetrate a SOL up to 700 yards but not beyond. The hull thickness of a SOL would be around 2-2.5 feet and I have seen 1.5 feet for standard frigates and 1.75 feet for USS Constitution (with extra strong oak used) The heavier guns seems to have a penetration of 4-5 feet at around 100 yards or so.

At least there is some physics we can be pretty sure of, and that is the relative difference in penetration based on difference in caliber. That same relative difference also works with ballistic coefficient.

I have converted the diameters of various gun weights with the 6# set at 1. Note that this is UK pounds exept the 36# French gun that is more like 39 UK pounds. The numbers in the brackets are the difference squared to show the overall surface area of a hole. An attempt of showing number or size of splinters.

6# 1 [1]
9# 1.15 [1.31]
12# 1.27 [1.59]
18# 1.44 [2.1]
24# 1.59 [2.52]
32# 1.75 [3.05]
36# 1.87 [3.48]

So a (French) 36# should have 1.87 times the penetration of a 6# at equal velocity. It will also move 1.87 times further before losing the same velocity compared to a 6#. For the 36# versus 24# difference it would be 1.87/1.59=1.18 and it might be able to penetrate a SOL at 900-1000 yards (if we base it on the US test)

There also seems to be an odd effect with penetrating wood, as the best way of producing lots of splinters was to have a shot with just enough velocity to penetrate. If it moved fast it would just make a neat hole. I don't know how to explain that except maybe that the violent(fast) impact would push wood more to the side, while the slow impact would be better at pushing the wood forward.


CBR