Oh I know the existed but they never seemed to take off as commonly seen or used weapons. Besides I find the Final Fantasy seriousness of the weapon to be far more amusing than the clumsy real life attempts to make it work. Sort of like the shield gun. Though I think my favorite is basically the "Muggers Swiss Army Weapon" The Apache Revolver.
Who watches the watchmen?Bullet tumble can be caused by a number of different things, including a long-thin profile relative to bullet mass, a relatively heavy base compared to a lighter weight tip, and a very slow spin rate when fired out the barrel.
Bullet tip design is a bit complicated, since a blunt tip is more likely to start tumbling than a pointed one, but pointed tips tend to be lighter in weight (which also contribute to tumbling), so to ensure this effect you need a relatively light weight yet blunt tipped nose.
I'm done trying to sound smart. "Clear" is the new smart.Actually heavy rounds can be made to tumble just as easily as a lighter round. While weight balance is important in that it affects round stability, overall weight is less of concern. Bullet shape and composition can impact how stable a round is not only in flight from the chosen weapon but also it's stability at impact. The twist rate of a rifle barrel can also impact a bullets stability.
A good example would be the ammo originally designed for use in the M-16 before the US military altered the rounds structure and powder load. The original round was noted to viciously tumble after penetrating the target and most gel shots show it doing just that. It penetrates a few inches then rapidly loses that stability and begins to yaw and tumble rather violently.
The old M-855 round that became the US defacto round for quite some time was an inherently very stable round both in flight and at impact. Part of that was because the round is designed to defeat both Soviet Steel helmets and the lighter more common forms of Soviet made body armor. So it needs to strike tip on to the target as much as possible. The downside to this is that at longer ranges the round both fails to fragment like it does at short range and has a fairly regular tendency to fail to tumble and "ice pick" through the target especially if the shot is a dead on impact. The more angle relative to the impact surface the more likely it is tumble.
You can design a round to tumble with fairly good reliability on impact. A good examples is the AP 5.7mm military/police only ammo. Shortly after it penetrates through soft body armor the round loses that stability and begins to tumble very sharply, typically at an upward angle. How you go about that depends as noted by De Marquis a wide variety of factors and there is no one simple answer.
edited 22nd May '18 6:38:44 PM by TuefelHundenIV
Who watches the watchmen?Ah, interesting.
Now that I think about it, it makes sense that an elongated bullet tends to tumble on impact more, from the tail's leverage- But elongation also increases sectional density, which helps with penetration, which sounds a bit contradictory. Seems like it is a rather complex combination of factors. (This would also explain why tested flechettes supposedly got deflected by things that regular bullets would've gone through)
Making the bullet heavier in the back also helps with external ballistics from what I understand, so no problem there.
What I have in mind is near-future ammo optimized for efficient aerodynamics and penetration of body armor, as well as being cheap: So regular bullets are mostly hardened steel, with a copper driving band and a tiny tip of some extremely hard synthetic material. To make bullets meant for less well-armored targets, the tip's installation is simply skipped(or a flimsy plastic tip is installed instead), leaving them with a small dimple at the front, or possibly a hole leading into a very small hollow; This should have the same effect as a flat tip for less frontal weight. The bullets are very elongated, which requires a high spin rate, but there could be guns whose spin rate is on the lower end of the acceptable range.
So it seems to make sense. Thanks.
edited 23rd May '18 1:36:38 PM by ManInGray
Man In Gray: You could borrow page right from today. The M855A1 has good performance against both soft and armored targets up to a point. The round has demonstrated an ability to defeat Level III Armor steel hard plate inserts. Which makes it effective against a variety of targets short of well protected APC's and the most heavily of armored of wheeled vehicles. There is also a 7.62mm variant of that round as well.
Who watches the watchmen?I did base them on it at first, giving them the same ratio of weight to length, because of the rigidity it gets from lacking a lead core.. But armor is only going to get better and more common; Steel's far greater strength would help penetrate it, and the difference in density isn't very large. If they could make mostly-aluminum bullets work by making them ~5.8 calibers long and properly shaped
, I'm sure this would too- The length I'm considering is either 6 or 7.
Tungsten is expensive, though; This is for the standard, general-purpose ammo.
The dedicated AP rounds would have subcaliber tungsten projectiles. And since the cartridges are already telescoped, I was thinking that some of the space freed by having a smaller projectile would be filled with extra propellant...
Tungsten isn't that expensive. Keep in mind we use this ammo in machine guns on a fairly regular basis. It isn't taking up any significant amount of space. It is still in the caliber it is made for. 5.56mm, 7.62mm, and other projectiles with modern black tip AP are still the same caliber.
Who watches the watchmen?Could a rocket fighter ever have been an effective weapon? When would a good POD for this be and how would a rocket fighter perform against a jet fighter?
Perhaps the rocket fighter might make use of an Aerospike Engine
to increase fuel efficiency and reduce the amount of fuel for needed for a mission?
edited 28th May '18 7:17:26 PM by zepv
The solid fuel rocket fighter concepts were never a great idea. You have a fuel source you can't control which means it burns as hard and as fast as it can non-stop. With liquid fuel you can adjust velocity and more easily control the burn and fuel feeds.
Where the solid fuel rockets came in handy was assisting heavily laden aircraft in taking off from run ways. The RATO bottles were powerful attachable rocket boosters.
edited 29th May '18 2:46:09 AM by TuefelHundenIV
Who watches the watchmen?Because a rocket engine needs to carry it's own oxidizer, it's always going to be less fuel efficient than an air breathing rocket. You might get more maximum thrust. Scratch that, you WILL get more maximum thrust but you'll run out of fuel in less than an hour. Often, it takes longer than that just to get to the battle.
That being said, this is only a problem if your Only engine is a rocket. If you've got turbojet primary engines you can use a rocket as a secondary engine for high altitude or a panic button to escape a dangerous situation.
Solid fuel rockets for the reasons Bel listed are very good at boosting almost anything to high speeds but can also be used for some intense braking. The US created an experimental aircraft called the YMC-130H. They were able to take off and land in less than 600 feet of runway clearance. The only reason they are not around still is because they were experimental craft created for a single mission and one of them suffered a notable accident during testing. They ran out of money and time shortly after that.
edited 30th May '18 8:33:46 PM by TuefelHundenIV
Who watches the watchmen?The only really reliable way to get sufficient oxidizers into solid fuel rockets is for it to be part of the fuel mix.
The Erkanoplanes technically worked but politics and a loss of the need for the planes helped beach them. The key factor for those craft was their speed over water.
When you start talking air breathing engines the tech we use now and even back in the first days of experiments with jet propelled aircraft before WII used liquid fuels.
edited 30th May '18 8:43:37 PM by TuefelHundenIV
Who watches the watchmen?You also can't take a liquid fuel rocket, add some intake vents, and expect to save on oxidizer. Modern jets use turbine driven compressor blades in order to function where as a rocket uses pure oxygen in liquid form.
Basically, you'd need to design a totally new rocket- turbojet hybrid for this.
edited 31st May '18 7:58:24 AM by Belisaurius
Just out of curiosity, when people state the energy density of some type of fuel, do they just state how much energy you get from combustion of a certain quantity in air (thus including the energy contained in the oxygen involved in the reaction) or do they somehow calculate the literal energy density, just the joules from the fuel and subtract what came from the oxygen during the combustion?

I see your going all final fantasy on us now.
Who watches the watchmen?