1. Impact velocity varies depending on distance, something between 300-350 m/sec. 2. We measured unrestrained recoil (no breeching) at 7.65 meters for the service load, 9.5 meters for the overpressure load. Recoil speed for the service load is slightly over 2 m/sec. 3. We are using a black powder made to our specification by Wano in Germany. It is the same component recipe as the original Swedish powder, although it uses modern distilled charcoal and manufacturing techniques, so should have up to 60% more "push" than 17th-century powder. We have compensated for this somewhat by using a large grain size, which slows deflagration. The result is a powder that is reasonably close to the original, but there is no way to know how close. 4. Original guns were often used to fire salutes, with a short stainless steel liner in the muzzle and electric ignition. No trials were made with live ammunition, although metallurgical analysis suggests that the guns would survive it. 5. Video of the full trials, including shooting at a replica section of ship, will be made available on 22 October - watch CNN!
We have now completed the firing trials, after a total of 54 rounds (including the three proof rounds on October 2). We discovered that the gun has an effective range (in terms of being able ot hit something the size of a ship) of up to 1000 m, with extremely good penetrating power. Two examples of the latter: 1. A low velocity (reduced charge) round fired on the long-distance range traveled 700 meters before hitting the gournd, skipped and travelled another 200 meters before hitting a steel I-beam which was used as a support for a target frame. The ball punched a hole through the I-beam. 2. The first round fired at the ship side punched through 50 cm of oak, traveled another 400 meters, struck the range perimeter road, flew another 100 meters through the forest and then through a pine tree trunk 40 cm in diameter.
In fact, we found it difficult to get a round not to penetrate the hull. Even with a reduced charge of only 1.1 kg (a third of the service load), balls still went through both planking and ceiling. The only round actually stopped by the hull was a scissor shot which struck the wale, althoght his round cut the wale in half and shattered the framing behind it.
The chain shot worked as advertised on the sail, and the two canister rounds (wooden tube filled with 215 .71 cal musket balls) made a cone of death about 3 meters wide at 35 meters range. Spike and scissor shot were surprisingly effective without damaging the gun.
All in all, a very successful test! A book will be forthcoming in 2015.
I didn't expect such low loads of powder to keep up that kind of penetrating power, especially at that range. So really, the sides of a warship of this time wouldn't be too protective of the crew, except for fire coming from small arms, or maybe canister shot. Although I am not sure about the canister shot. Would be interesting to hear about the results of one of those at the replica side.
We fired a canister round at the side of the ship: 215 .71 cal lead roundballs in a wooden canister, weighing about 9 kg total. At 35 meters distance, some of the roundballs went through the outer layer of planking (c. 75 mm thick), so we would expect them to have gone through the bulwark planking quite easily. They are soft lead, and deform readily, so what they would do on the other side of the bulwarks is difficult to say, but it would not have been pretty.
Concerning Tom's lion mask on the gunport lid, we bullseyed that on the third round fired at the hull copy. It destroyed the mask (three big pieces plus fragments), went through the the gun port lid, shattering it, then through the planking and into the edge of the waterway. It tunneled 50 cm through the waterway before deflecting dowward off a bolt and was found lying on the ground about a metere inside the ship. So it took something like 75 cm of oak to slow the round down.
A lot of the penetrating power is down to the size of the ball. A 24-pound ball has more mass relative to its impact area than a smaller ball (65 g/cm2, compared to 52 g/cm2 for a 12-pounder, or only 32 g/cm2 for a 3-pounder), so for the same velocity, the larger ball has more impact energy for each square centimeter of hull it strikes. This is why everyone wanted bigger guns. Even with lightweight bastard pieces such as the Vasa 24-pounder, which cannot fire as large a charge as a full-strength piece, the ball still has more than enough energy to go through a couple of feet of oak ship structure.