Galleons artillery: aren't its too light for shells?

The problem is, that on Earth the shell gun calibre in XIX century started from 50-pounders.

Lodging a shell in the hull (or partial penetration) is actually the most effective outcome of a round being fired because when the shell explodes, it is going to blow a far larger hole in the hull than it would by merely passing through

I knew that perfectly, but you need to achieve at least that. And with small calibre shells - they would simply bounce away on most case.

The explosive shell weighs less than the corresponding solid shot in a given bore size, so the carronade would actually have improved ballistic characteristics (increased velocity) when firing them.

And they exploded in barrel. The problem is, that the shells of XIX century design (round) simplu cannot sustain the acceleration of the solid shot. You cannot have enough kinetic energy by shooting them fast; they are unable to stand the acceleration.

The Paixian guns weren't created as "large calibre, slow muzzle velocity" for nothing. They were able to fire big shells (big enought to have sufficient kinetic energy) on low speed (so the shells wouldn't explode in the gun). The 30-pdr long gun would be able only to either damage itself with pre-detonation, or fire shell with insufficient speed to penetrate.

Dilandu wrote:The problem is, that on Earth the shell gun calibre in XIX century started from 50-pounders.

Lodging a shell in the hull (or partial penetration) is actually the most effective outcome of a round being fired because when the shell explodes, it is going to blow a far larger hole in the hull than it would by merely passing through

I knew that perfectly, but you need to achieve at least that. And with small calibre shells - they would simply bounce away on most case.

The explosive shell weighs less than the corresponding solid shot in a given bore size, so the carronade would actually have improved ballistic characteristics (increased velocity) when firing them.

And they exploded in barrel. The problem is, that the shells of XIX century design (round) simplu cannot sustain the acceleration of the solid shot. You cannot have enough kinetic energy by shooting them fast; they are unable to stand the acceleration.

The Paixian guns weren't created as "large calibre, slow muzzle velocity" for nothing. They were able to fire big shells (big enought to have sufficient kinetic energy) on low speed (so the shells wouldn't explode in the gun). The 30-pdr long gun would be able only to either damage itself with pre-detonation, or fire shell with insufficient speed to penetrate.

Is there really a problem here? Whatever might be true at the battles of the Markovian Sea and Ithyria, things have moved on. The future probably looks more like those rifled cannon Sharpfield used to take apart that battery at claw Island.

Don

jtg452 wrote:Penetration in its' most basic form is a question of momentum (mass times velocity squared). (Please note the phrase- "most basic form". I fully realize that there's many more variables that have to be considered when dealing with penetration but for the question at hand, they are secondary to the explanation of the basic concept.) Heavier projectiles carry that momentum longer than lighter ones (following Newton's, "An object in motion..." and they have more mass to hold that motion) but a lighter, faster projectile has more velocity (but less mass to resist shedding it) that it can shed in the target before being brought to a stop by the target's resistance to its' passing through it.


The 'long guns' or cannons that fire smaller projectiles would have had enough barrel length to obtain the velocity needed for penetration. Black powder has such a long burn time that it takes a long barrel to generate higher velocities. To translate it into small arms, that's why the old single shot buffalo guns of the 1870's had 28 to 34 inch barrels instead of the 20 to 26 inch barrels that are more common today.

The carronades relied on the mass of the projectile for close range penetration due to the low velocity caused by their short barrels. Note the 'close range' part, they were short range guns during the Age of Sail on Earth with an effective range of only a few hundred yards. At very close range- say 50 yards or less, where the British liked to fight- the loss of velocity was minimized and they were devastatingly effective even when using solid shot. They weren't referred to as 'Smashers' for nothing. 'Long range' for a carronade would have been a hundred yards and the max effective range at sea was more around 200 or 300. That's not to say they weren't fired at longer range, a 57 pounder ball hitting a hull on a hop is still going to do some damage even if it never penetrated by producing showers of splinters on the inside of the hull.

The explosive shell weighs less than the corresponding solid shot in a given bore size, so the carronade would actually have improved ballistic characteristics (increased velocity) when firing them.

As previously pointed out, with the explosive shell, full penetration of a hull isn't necessary or even wanted if the objective is to sink the opposing ship. Lodging a shell in the hull (or partial penetration) is actually the most effective outcome of a round being fired because when the shell explodes, it is going to blow a far larger hole in the hull than it would by merely passing through. If the shell has a 12 inch diameter, then full penetration results in a roughly 12 inch hole that can be easily plugged. If a 12 inch diameter shell lodges in the hull and explodes, it could blow a hole 6 feet or more across (leaving the secondary damage to the internal structure and crew aside). You aren't going to 'plug' that kind of damage by ramming a piece of wood in the hole like a cork in a bottle.

Charis has superior ships and they know it so they follow a line of thinking that's more like the British when in a fleet engagement- namely that if they sink an opposing ship by shooting 'between the wind and water', that's one ship less they have to face. They don't necessarily want or need to capture opposing vessels. If they did, they would use a different style of fighting that is more like the French's attacking at longer range and shooting for the rigging with chain or bar shot to disable the vessel but keep the hull in one piece.

Where you talk about black powder and barrel length, you have it backwards. Black powder burns faster than cordite. WW2 guns could be up to 50 calibers long while black powder guns rarely were longer than 20 calibers long. Anything longer than 20 would start having problems with friction slowing your shells after powder burnout.

You may be right w.r.t. Earth history but we have clear textev that shells were subject to much experimentation in the development phase such that shells would be likely to penetrate the hull upon impact but be retained by the hull inside after that. They were, according to textev, tuned to produced precisely that effect. I know of no textev which points to superthick sides on galleons such as we see in Earth's navies of the Napoleonic era. Nor does there appear to be any live oak around!

You may not agree with the textev (see long discussion about exactly these points in AMF, Year of God April 894, Chap 5), but it was pretty clearly provided by the author.

Dilandu wrote:Just thought about that. The battle of Markovian Sea has been won largely because of Charisian explosive shells for their galleons guns.

But.

As i recall, the charisian guns of this era was either a long 30-pdr, or the 57-pdr carronades.

Are those guns really could work as a shell guns? The main problems with shells in naval warfare on Earth, if i recall correctly, was their insufficient weight to penetrate the enemy hull, and inability to survive the large acceleration. This why the shells wasn't really a significant part of naval warfare before the Paixhans gun.

The Paixhans gun combined large calibre (i.e. heavy shell) with low muzzle velocity (i.e. no problems with acceleration). But as i recall, all shell guns was large, seven or more inches, with shell of 50 and more pounds. Still, they weren't carronades; they have much larger muzzle velocity.

So. Would the small Charisian shells really work so good? I have doubts that they would be able to penetrate hulls of NoG galleons - their shells seems too light to do the job. Or i made a mistake somewhere (must admit, i haven't re-read AMF for some time)?

It is possible to create a shell or canon ball that fires a projectile designed to burns instead of explode. if fire is so dangerous, then while explosives are always dangerous, the fear of fire could be very useful. SAy a thermite canon ball was possible, thermite can melt metal, on a wooden ship imagine it, it could hole the ship and burn it at the same time.

SYED wrote:It is possible to create a shell or canon ball that fires a projectile designed to burns instead of explode. if fire is so dangerous, then while explosives are always dangerous, the fear of fire could be very useful. SAy a thermite canon ball was possible, thermite can melt metal, on a wooden ship imagine it, it could hole the ship and burn it at the same time.

Yes there are various incendiary shells but they could difficult to use in this event. Thermite is a non-starter for this as it is very difficult to start burning in an uncontrolled manner. Phosphorus has health problems and is Proscribed. Wikipedia has an article under "HEI"

This whole subject is one I wish RFC would weigh in on. As has been pointed out Dilandu's argument doesn't come from textev, but by extrapolating from experience in our own time line, which, although useful, isn't decisive for Safehold.

Without calling Dilandu's research into question, I have difficulty imagining cannon shot fired at forty yards simply boucing off its target without penetrating. That is pistol range, suicide range.

i did read that section in AMF referred to up thread, but there was no textev about how thick a Safehold galleon'S hull is.

So, unless we are talking about handwavium which is an author's privelige, I don't see a way of answering the question posed in the heading of this thread.

don

n7axw wrote:This whole subject is one I wish RFC would weigh in on. As has been pointed out Dilandu's argument doesn't come from textev, but by extrapolating from experience in our own time line, which, although useful, isn't decisive for Safehold.

Without calling Dilandu's research into question, I have difficulty imagining cannon shot fired at forty yards simply boucing off its target without penetrating. That is pistol range, suicide range.

i did read that section in AMF referred to up thread, but there was no textev about how thick a Safehold galleon'S hull is.

So, unless we are talking about handwavium which is an author's privelige, I don't see a way of answering the question posed in the heading of this thread.

don

I don't have time, for a lot of reasons, to engage in another epic debate with Dilandu on this topic, so after this post you will not draw me back out of hiding to argue the case with him. I composed this off-line because my intranet connection is really bad just now, and I haven't gone back and re-validated everything in the post after reading back over the entire thread. Nonetheless, I think the following should explain the situation on Charis.

I will note that there is a great deal of confusion about the difference between black powder and high explosives. The truth is that black powder's natural burning rate is actually lower than that of nitrocellulose. Because of the difference in the two propellants' characteristics, however, black powder does produce a bigger pressure spike than nitrocellulose. The advantage of granular black powder over meal powder is less that the powder burns faster (in fact, the individual grains burn slower) but that it burns more completely because the air spaces between the individual grains are larger. Note that what we are talking about here happens so quickly that terms like "slower" don't really have much meaning as far as human senses' ability to detect the difference. That is, the entire combustion process is completed so rapidly and the propulsive/energy liberation effect is so enhanced by the greater efficiency of the granular powder's combustion that granular powder produces a bigger spike — for all intents and purposes, an apparently "faster" explosion — than meal powder does.

The primary difference between black powder and nitrocellulose is that nitrocellulose contains no noncombustible components. That means that nitrocellulose burns much more completely, producing about three times the gas volume (energy) of an equal weight of black powder because of how much of the black powder is wasted in smoke and powder residue — the "ash" left behind by those noncombustible elements, if you will. In addition, it's much more difficult to regulate the combustion rate of black powder. It burns at the speed at which it burns, although you can slow it down somewhat by using slower burning charcoal. This is what the Charisians have done in formulating "brown powder," similar to our own late nineteenth century "cocoa powder." There are distinct limits, however, and it is actually easier to introduce moderators into nitrocellulose to slow down the gas velocity produced.

Among other things, this is the reason you can use a longer barrel with nitrocellulose. Gunpowder – whether black or brown — can't be adjusted or "tuned" the way nitrocellulose can. In theory, a longer barrel means that the projectile will spend more time with the expanding volume of gas behind it accelerating it down the bore. In fact, because gunpowder "spikes" and is so much less inherently efficient than nitrocellulose, after a certain point, friction offsets the advantage. Since nitrocellulose produces three times the volume of gas and since its burn rate can be adjusted to generate that volume more gradually (note that "more gradually" in this case is a purely relative term; that gas is being generated damned quickly whether it comes from black powder or cordite ) the longer barrel does equate to a longer — and greater — acceleration.

And now to the discussion of 30-pounder shells.

With all due respect, Dilandu has this one wrong.

It’s been stated a time or two in the books that the Charisian 30-pounder is actually much closer to a 32-pounder. The solid shot for the gun actually weighs 31.81 pounds, if you’re interested, and the explosive shell weighs 17.9 pounds with explosive charge. In other words, it’s an 18-pounder for all intents and purposes. Now, it is true that an approximately 6-inch diameter round shot which weighs 18 pounds will lose velocity faster than a shot of the same diameter which weighs 32 pounds, but at the ranges at which naval engagements are fought on Safehold (or, at least, the ranges at which they have been fought so far), the differential in velocity-bleed is not going to have a significant impact on the ability to penetrate the sides of what are essentially big frigates, not true ships-of-the-line.

An explosive shell from a 30-pounder will not have the same penetration as a solid shot from the same weapon. Dilandu is perfectly correct about that. And the lack of penetration of a 30-pounder shell when bombarding targets ashore has been commented upon in the books many times. They are, however, fully capable of penetrating the 12-18”-thick sides of a typical Safeholdian galleon from ranges of several hundred yards, and that’s the range at which naval actions are fought using sail-powered vessels and muzzle-loading smoothbores. In theory, battles could be fought at significantly longer ranges, and that may well happen in the case of maneuvering duels between single ships on each side, but it is not the range at which any of the major engagements so far described in the books have occurred.

I can’t really speak to French practice, because I’m not as familiar with the original sources as I am where American and British practice is concerned. I’m most familiar of all with the development of big-bore, black powder shell guns during the Dahlgren-Rodman period here in the US. Dahlgren favored 9” and larger shell guns in no small part because he was also looking at the smashing effect they would have firing solid shot against targets for which shells were not the preferred ammunition. He also determined, on the basis of extensive testing, that the ideal muzzle velocity was one which permitted the shell to penetrate the target’s side but not to pass clear through it, and he achieved that by reducing the powder charge when firing shells. With solid shot he wanted to pack in the most kinetic energy he could get; with shells he wanted to slow the projectile down — the “big and slow” Dilandu mentioned in an earlier post.

Now, there are other reasons besides the smashing effect of a bigger solid shot to prefer a 9” shell to a 6” shell. A 9” shell will sustain its velocity longer, all other factors being equal, and carries a larger bursting charge, which makes it more destructive. Unfortunately, the Charisians had a whole bunch of existing 30-pounders and no 9” long guns available, so they had to design shells they could fire out of their existing weapons. They never thought (and I never said they did) that this was the ideal weapon; it was the one they had available in quantity and it was enormously superior to anyone else’s weapons capability even with the smaller than ideal shell. If you will recall, there have been multiple references to the fact that the 57-pounder (the Charisian navy’s standard heavy carronade) is considerably more destructive over its shorter range than the 30-pounder is, and the disparity increases when both weapons are firing explosive shell. The 57-pounder has a 7.3” bore, fires a 57.35-pound solid shot, and a 31.55-pound explosive shell. This means the shell from a 30-pounder weighs only about 56% as much as one from a 57-pounder, although the longer 30-pounder can deliver its round to a greater range.

If Charis were not converting to rifled guns, then Howsmyn would probably develop something closer to the 9” (and bigger) Dahlgrens and Rodmans developed in the U S during the nineteenth century. Charis is going to rifled artillery, however, and even the broadside 30-pounders have been fitted with rifled liners. Using the studded rifling system which was adopted several books ago, a “30-pounder” fires a 100.6-pound cylindrical solid shot and a 67.19-pound explosive shell. There is also a 90.79-pound “armor piercing” or “battering” shell which has better penetration than the standard explosive shell but a considerably smaller bursting charge which, coupled with the thicker shell walls greatly reduces the explosive effect of a hit.

As for premature detonations in the barrel, which I believe Dilandu also predicted (I’m working off-line right now and can’t really consult his earlier posts), that’s also a non-factor. Black powder-filled shells have an unpleasant tendency to explode almost instantly on impact and — on occasion — to explode prematurely inside the gun barrel. There are several reasons for this, but the primary one is the friction between the grains of powder when the shell is suddenly accelerated or decelerated. The US Army’s Parrot Rifles had a particularly bad record for bursting barrels and shells that prematured on their way down the bore, although the Army’s ordnance manuals indicate that when the gun was properly maintained and the shells were lubricated such problems were enormously reduced.

In the case of the shells manufactured for the Imperial Charisian Navy (and Army), the shells are filled before they are shipped to the units which are going to actually use. Note that this is contrary to the practice of most navies in our own history at least until into the last half of the nineteenth century. One of the reasons they are shipped already filled is that after they are filled, the powder charge is stabilized by a pour of liquid sulfur. This doesn’t close up the gaps between the individual grains of powder, so friction-induced premature explosions are still possible, but it binds the entire mass of the powder charge sufficiently to hugely reduce that possibility.

Again, don’t think that I am saying — or that I’ve ever said — that a 6-inch smoothbore firing an 18-pound explosive shell is as effective as a 12-inch smoothbore firing an explosive shell that weighs 140-pounds. All I’ve said is that it can be done, that the explosive shell is a great deal more destructive to a wooden-hulled ship than a solid shot of the same size, and that Charis had several thousand thirty-pounders capable of firing the lighter shell and didn’t have the time to design and field and entirely new broadside weapon when the ICN needed an explosive equalizer for the numbers of ships about to be thrown at the Empire.

For field gun employment, a 30-pounder is about the biggest muzzle-loading smoothbore anyone wants to drag around a battlefield. In fact, it’s really too big to be as mobile as the field artillerists would prefer, which is why the 12-pounder is the standard field gun size. Nonetheless, a 30-pounder shrapnel shell speaks with a great deal of authority, and the straight HE bombardment round from a 30-pounder is far more destructive than one from a 12-pounder. Again, this should not be taken to suggest that I am equating the effectiveness of a 6” smoothbore’s spherical shell with the effectiveness of the cylindrical (and much heavier) shell fired by a rifled angle-gun.

Thank you for that explanation RFC.

Thanks for explanation, RFC. Still have some doubts, but definitely didn't want to start another discussion.