How to Rifle your Gun

A guide for the incredibly niche detailing task of making a rifled gun in FTD; something that the majority of FTD users probably don't even want to ever attempt and something I'm only posting so I can explain how I made the gun on a wheeled tank destroyer I made because several people have asked how I did it. So this guide is for you, so you can understand too and avoid making a gun this way since it's too complex and painful.

How to make a Rifled Gun in From the Depths

This will be a step-by-step comprehensive guide on how to give your From the Depths gun custom rifling, like on that wheeled tank destroyer I made, because multiple people have asked for the method on how I did this and I should probably make it public so all of you understand just how much you don't want to attempt this.

Step 1: Reconsider

Do you really need to stick rifling on whatever gun you're making? It's an incredibly niche and unnecessary detail. You can get away with just decorating some alloy poles onto your guns with a black circle at the end and that'll look good enough for a decorated gun. Or you could go with the even easier approach of just covering the whole ass barrel with a gun130Single Cas Barrel. You could just click away right now and pretend you never saw this guide.

Both gun styles on HMCS Nova Scotia.

The only reason I even came up with this method in a first place was to see if I could turn a clearly losing and stupid argument on the From the Depths Discord, one where a person suggested that an alloy pole decorated barrel would look better with the gun130Single Cas Barrel, and figure out a way to make an actual compelling case for it. This was clearly not a good decision nor a good reason to make a bad decision. I would recommend not making the same mistake I made.


Now, if you're past that first half-step, you also need to consider if the vehicle you're building even would have a rifled gun. Are you building a warship? Then, assuming it has a gun of a size which could be considered at least "semi-significant" and isn't from the age of sail (note: some late age of sail ships did carry rifled guns), then it probably has a rifled gun.

If you're building a tank however, you have to be careful. If it's a modern tank, then unless you're in a third world nation like Somaliland, Mauritania, Britain, or Zambia, you've either retired all of your tanks with rifled guns or at the very least have a more recent tank with a smoothbore gun. If the tank is from the mid-Cold-War or earlier, then it might have a rifled gun and you can almost justify reading the rest of this guide.

Step 2: Get Advanced Mimic UI

If you don't get this mod, the task of making rifling in From the Depths goes from "bearable-adjacent" to "masochistic." So get the mod, if you haven't already.

If you happen to be on the Alpha branch, then I'm sorry, you're ♥♥♥♥ out of luck. It doesn't work on Alpha from what I've been told. So scram, and come back when you're not on alpha branch anymore. (note: sometimes it updates for Alpha branch, so if it works then I guess just ignore that part?)

https://steamcommunity.com/sharedfiles/filedetails/?id=1988528996

Step 3: Define the Gun

So you've not turned back yet, which means you're beginning to commit to the incredibly poor decision of trying to make a rifled gun in From the Depths. At this point nothing I say other than describing the method itself is likely to turn you back, so I guess at this point we just have to keep going.

So, the first thing we have to do is define the gun.

Google says the definition of gun is:

noun
1. a weapon incorporating a metal tube from which bullets, shells, or other missiles are propelled by explosive force, typically making a characteristic loud, sharp noise

2. muscular arms, well-developed biceps muscles

verb

3. cause (an engine) to race


STEP 4: Build the Gun Ok, now that we're done defining our gun... oh, wait, we don't have to define gun, but rather the characteristics of whatever gun you want to design.

The first 2 important characteristics are the diameter and length of your gun. If you are reading this guide I assume you know how to build a gun in From the Depths and how to define bore diameter if you don't want a gun quite as large as the gauge increasers get you. My wheeled tank destroyer uses a 117mm wide 5m long barrel, and for this demonstration I will use a 250mm 10m long barrel.

The other important part you need to define are the characteristics of the rifling. Now, normally rifling is defined by how long of a distance it takes for the twist to do a full revolution, but we're going to throw that definition out since it doesn't work well for From the Depths.

So, for From the Depths rifles there are 3 important characteristics:
1: How many grooves there are. Do remember that for each groove there is a piece, so don't exceed 32 unless you want the From the Depths police to come after you (AKA a significant increase in build difficulty and complexity that this guide will NOT cover how to solve).
2: How long is each "section" of rifling. The bigger your bore diameter the longer your sections should be. I'd probably try to keep this to 1 divided by a fairly low integer, something between 1/1 and 1/10.
3: How many degrees each section rotates by. I suggest keeping this to a small number of degrees. It is probably best to divide 360 by the number of grooves there are, and use that number. Or you could multiply that by a whole number. Technically, if you like pain, you can divide it by a whole number, preferably something small like 2 or 3, but you'll have to perform an extra step later on.

My wheeled tank destroyer has 24 grooves, 0.2m sections, and 15 degrees of rotation, which I'll now refer to as 24, 0.2, 15.

For my example here, I'm going to use 20 grooves on half-block (0.5m) sections. 360 divided by 20 is 18, which is the degrees I'll have the grooves rotate by per section. As such, I am using a 20, 0.5, 18.

Step 4: Build the Gun

Build your APS cannon. If you need me to tell you how to do this, then you should probably be reading an entirely different guide to this. Or be looking at the ingame tutorial. If you don't know how to build guns in general in this game, then this is far, far removed from a guide even remotely resembling anything close to one that's written for you.

Also, I'd recommend avoiding heavy barrel usage here, unless maybe it's a shipborne main gun for a heavy cruiser or battleship.

You can probably adapt these instructions for a CRAM cannon if you really want to, but I'm going to be assuming APS usage here

My example gun:

Step 5: Put Down the First Piece of the Land

So you may be reading the title and getting confused. "What the hell is a "Land???"" you may ask. It's simple. "Land" is the term used for the ridges in the rifled barrel; basically the opposite of the grooves. This is the part you must build.

To start, first place a block directly above the barrel. Make sure connection rules aren't applied, which can be done by pressing "backspace"

Use ctrl-x to enter in the decoration menu on the furthest forward barrel of the gun. Check the "hide original mesh" option, and on the decoration search for Mimic: Empty and use that on the decoration. This will completely hide this section of barrel.


Now go to the block and enter it's decoration menu. Hide its original mesh too. On this decoration, select a 1m pole of any material (except glass honestly). Move it down 1m, so that it's centered with the barrel, and change its Left Right and Up Down scaling to the same diameter as the shell of the gun measured in meters. If you want you can make it a tiny bit smaller, as rifling does squeeze the shell, and you will be using this as a measure for the rifling.

Set its forward backwards scaling to the same length as the section you previously defined. Then move it forward along the gun until the front of the decoration aligns with the edge of the block.

In my example, I have a 250mm cannon, so I have a Left/Right and Up/Down scaling of .25, and a section length of 0.5 meters, so I have to change the Forward/Backward scaling to 0.5, and shift it 0.25m forward to align the deco front with the block front


Now the next step is to really start making use of the settings in Advanced Mimic UI. Chance your Amount of Increase (Angle) to whatever degree change in rotation you set. In my case, that is 18.


Now, add a new decoration onto the block. It is probably best to copy the pole to start, but it's not necessary. Set this second decoration to a Mimic: Cone. Set it so it's pointing either up or down (I'll use down), make it a thin cone, but maybe not the absolute thinnest setting. Thin but not quite anorexic. Make it slightly longer than the diameter of the pole. Place it aligned with the front of the pole.


Now, copy the cone, create another decoration, move it to the backside of the pole, and change it's roll by your degree change in rotation. If you set this setting in Advanced Mimic UI, it is one button click. You can pick either direction, depending on which way you want your rifling to roll.

It should look something like this:

Now, this was something I didn't do on my first attempt, but have now learned it probably would've been a good thing to do. Copy the forward cone a couple of times, and rotate each one by your designated degree change in rotation, once in either direction. You will be using these 2 to assess the width of your land.


So now let's actually add in our first piece of land. Exit out of the mimic editor on the block and now move onto editing mimics on the forward piece of the barrel. Take the mimic you already have there, and change it from a Mimic: Empty to either an alloy or metal plate, or an alloy or metal block. Although I guess you could try an applique panel if you really wanted to.

For my example, I'll use an alloy block, since it's easier to manipulate and seems to get small enough, but on my wheeled TD I did use plates.

Anyways, whatever you choose, start by setting it's Forward/Backward scaling to the same as your section length. Since this will technically be the hypotenuse to a right triangle of which the section length is one of the sides, be prepared to make this value slightly longer.

Next move the piece of Land to the same Forward/Backward positioning as the pole, and up or down far enough to be just touching the side of it.

Make the Up/Down scaling a small number, since you want it to barely be visible above the liner. For the Left/Right scaling, imagine more of them placed down at the tips of those extra cones you placed, and think about how big said groove would be. Scale this to however large you want said groove to be.

Now it is best to go back into the block and delete the extra cones for groove width determining. Leave the first 2 cones you placed though, and the pole.

Go back to the piece of Land you put down. Your goal now is to have the top centerline of this block or plate connect the tips of both cones while staying flush against the side of the tube. I would highly recommend going into "settings" in the "Other menu," where you already changed the increase in angle, and set all of these to extremely low values, like 0.05 or 0.01 for position and 1 for angle or something. You're going to need precision, and will likely have to manually adjust the positioning numbers for the mimic to get that even with the low settings.

Now, set the roll to half of your designated rotational degree change per section. In my case this would be 9 degrees.

Adjust the other positional values until it connects the tips of both cones. It should look something like this:


Oh, right, and recolor the Land decoration onto whatever color slot you want it to have. Best to do that now before we copy and paste everything (although there is always the "paint all" option you could use later if you missed this step and have now come running back to it when you realized you screwed up, as long as you aren't too late in the gun rifling process, at which point you're pretty screwed not going to lie).

Step 6: Creating Your First "Section"

So now that that first piece of "Land" is in we're ready to complete a section. Right now the guide is still there, and it's no longer needed. So delete the block above the gun and all the decorations on it. The only decoration remaining should be that one piece of Land, whether it be the block or the plate.

You're going to need to go into your decorations settings again, and set the Amount of increase (Angle) back to your standard rotation per section, and the Amount of increase (position) to 1.

Now place down a block somewhere else on the construct

And now, in a different spot, place down 2 blocks back to back.

Like this

Now go into prefab mode in the build mode, grab the barrel piece with the piece of Land on it, and paste it so the decoration is copied to the single block. It will appear a bit different in size because the scale effects of the gun barrels aren't being applied, but that doesn't matter.

If your intended groove count is even, then copy this block as a prefab, rotate it upside-down along the roll axis, and place it down. This should put a second piece of land directly above the first. If your intended groove count is divisible by 4, then use the prefab menu to copy the block again, roll it 90 degrees, and paste it again. Now you should have 4 pieces of Land


Now use the prefab function to copy and paste that block onto both of the 2 blocks in line.
It's time to use the Advanced Positioning tool.

Take the back set of decorations, move it forward by 1 so it appears in the same spots as the block in front of it, and then rotate it by your standard rotation per section, which should be 1 click of the button if you set it up properly in settings.

Now shift the tether point on the back block to the forward block.

You should notice this placed a second group of Lands slightly offset from the first, with a groove in between.

Repeat this process until you have all of the Lands and Grooves you want, and make sure to not accidentally double-up on decorations in the same space.

When you're done, it should something like this:
This is now a completed "section" of rifling. I'd recommend saving the prefab.

If you made the smart decision of taking 360 and dividing it by your groove count to get your standard rotation per section, then congrats! You can move onto the next chapter! If you took that number and multiplied it by a whole number like 2 or 3, then you're still done, and you also can move on. But if you're one of those who decided to divide the number by 2 or 3 or something, there's an extra step you have to do.

You need to create an additional prefab with the entire decoration set rotated by an additional half or third standard rotation based on whatever you picked before moving on. 2 additional prefabs if you divided it by 3. 3 additional prefabs if you divided it by 4. I think you get the point. You will need to alternate between these prefabs, in order.

Step 7: Putting in the Rifling, Probably with Spinclipping

So now that you're here with a prefabbed section of rifling which should align with itself when it's repeated, there's a couple ways things can go.

If you've done 1m sections with a reasonable number of Lands and Grooves, like 24 or less, thankfully you can avoid spinclipping and just place down your prefab on every barrel part, and skip ahead to the next step

If you've done some fraction of 1m, you are probably going to need to spinclip multiple guns together, unless you've done something like 15 Lands/Grooves over 0.5m sections, where you might just barely squeeze out a gun on the remaining 2 decorations per piece you'd get once you combine 2 sections per 1m of barrel piece.

Anyways, how spinclipping works, for those who don't know, is that blocks placed on subobjects can clip through the main constructible or any other subconstructible, and also only get blocked by any blocks on their parent object or subobject, but this latter part really isn't important here.

Simply put, if you need to put more than 32 decorations on every 1m section of barrel, then you need to spinclip multiple guns together to do it. And even at 32 decorations per barrel, that still doesn't offer you any to do any more than the rifling itself, so you'd still probably need 2 guns spinclipped together there.

First thing we'll need to do is change the amount of increase (Position) in the mimic settings menu to your standard rifling section length.

Next you'll need to copy and paste your gun, removing all decorations from it. Now, you will need it to be the same caliber and same barrel length as your main gun, and also have the same fire rate, although said same fire rate will be with much smaller shells, so you can optimize for that. Or, if you're in alpha, or in the future long after I typed this post, there is a checkbox which lets you turn off the recoil animation, which you can do instead. But if you're in alpha, I told you to get out of here on step 2, so go already. There's no way you're at step 7 without Advanced Mimic UI.

So, why do you want the gun to have all of these stats be the same? Well, if it's not the same diameter, it's going to change how the mimics look, so they no longer align. If it's not the same length, it will move at a different speed when aiming, becoming desynched. And if it can't shoot at the same pace as the main gun, then the main gun will recoil back after a ship whilst a bunch of decorations on the inside will just stay in place. Which, trust me, looks very weird.

So copy your gun, and delete that decoration on the barrel in the copied version.

Now make a shell for your main gun, or if you have one check what the reload speed is.

For your spinclipped gun, you're going to need a specific shell design. It needs a timed fuse, an HE head or body, and then, if you want to be material efficient 1 gunpowder casing, or space efficient 2 gunpowder casings. Set the propellant amount in the gunpowder casings as low as it can go, and the timed fuse as low as it can go while still giving the HE enough time to clear the vehicle to not damage it.


You then design your spinclipped gun so that with this shell it has a higher fire rate than your main gun. You then enter the gun settings, and restrict it to the same rate of fire as your main gun, although I'd probably very slightly restrict the main gun too just to make sure both have the exact same rate of fire in the end.

Now assess how many spinclipped guns you're actually going to need. You probably want to have 1 spinclipped gun for each section of rifling per 1m of barrel, with the main gun optionally taking the first set. For my example build, I could technically get by with only 1 spinclipped gun, but I'm going to make 2 and save the main gun for the outer casing decorations. For my wheeled tank destroyer, since it had 5 sections of 24 Lands and Grooves it wound up getting 5 extra spinclipped guns. If you're putting rifling directly on your main gun, do remember to remove that initial single piece of Land you put on it before you put the rest of the rifling.

Right now don't spinclip the guns, or even place them on the spinblocks. Just put them somewhere to the side.

For your first gun, whether that be your main gun or 1st spinclipped gun, take your saved rifling section prefab, and copy and paste it to every 1m piece of barrel.

For your second gun, place down your prefab, go into the Advanced Position editor, and move it back 1 rifling section length. Then prefab that and copy it to each 1m of barrel.

Repeat until all spinclipped guns are done.


Now put down a spinblock for each intended spinclipped gun. Prefab copy and paste the guns onto the spin blocks. Make sure you include an all-in-one local weapons controller on them! Hide every main block you want hidden with mimic: Empty decorations. Once that is done, save the gun you want the furthest in the subobject chain as a subobject, then place it on the next gun down, and save that, until all these spinclipped guns are stacked as 1 object, although without yet being spinclipped on the main gun. That'll be in step 8. Save the whole stack though.

Step 8: Completing the Gun

So now we must undertake the final steps to getting the gun to work. First work needs to be done to decorate the main gun, and then the spinclipped rifling can be placed on.

The first step is to delete the single piece of Land still on the forward portion of the main gun. The second thing is to place an entire section of rifling in it's place. If you decided to have rifling on the main gun object, then ignore the past 2 things, since it's already there.

Hide all gun sections with Mimic: Empty decorations quickly.

Put down a Mimic: Tube decoration on the gun. Scale it so the insides of the rifling just barely poke through it. This is your gun lining

'
And after this you just have to cover the outside of the lining by constructing the rest of the gun, with some decent thickness. More mimic: Tubes can be used, although gun130Single Cas Barrel is another good choice as well as a variety of the large and small jet engine parts. Do remember when decorating the gun that the gun will rotate around the center of the firing piece, but any decorations placed on the firing piece won't move with the gun. Any decorations placed on the mantlet will move with the gun, but will not be scaled to the same size of the gun. It is also probably smart to have a black circle somewhere towards the back of the gun, unless you're a complete masochist and want to model the breech mechanism properly.

Also, keep in mind while building to regularly check inside the gun, to make sure nothing is unwantingly clipping through into the hollow part of the barrel.


Once this is all done, delete the bit of rifling at the end of the gun (unless you have a design which leaves it in, or want to move it forward 1 section or something which is doable), and place the spinclipped set of guns below the main gun. Delete any other extraneous objects from this whole construction process as well. And with that, you're good to go!

Example gun

Gun on the Caribou, my first attempt at this style of gun and the reason I made this guide.

Step 9: Thanks for Reading

Thanks for reading this, hopefully now you're either well on your way to building a rifled gun in FTD or are crying realizing that this is way beyond your skill level and you're probably never going to have a rifled gun in FTD. Or maybe you're crying because of all the pain you know you'll experience trying to build a gun like this. I'm glad you at least stuck around to fully take in how difficult this is, but hopefully I made it at least presentable and have given many of you a way to attempt this!

Anyways, that's it from me. This took a whole day of my life to type up.


Workshop links to the vehicles used here:

NN-15-G117 Caribou
https://steamcommunity.com/sharedfiles/filedetails/?id=2827550093

HMCS Nova Scotia:
https://steamcommunity.com/sharedfiles/filedetails/?id=2806227977

[fraz12]

yo that's crazy putting britain on the same level as mauritania and zambia

[rojogames371]

Did you call Britain a third world country?
You BASTA-

[marcel700]

i wonder how mutch time goes intoo all of this XD

[Noname117]

@Slim Pickens

You probably could, but I wanted to impress people with nearly full-length rifling. Besides, there's now a way to jam all the decos onto the same gun barrel instead of clipping like 10 together or something.

[Slim Pickens]

Maybe it can be made a little bit simpler (though honestly the finickiest part of making that first section prefab is unavoidable) by reducing the visible length of rifling. Place a couple increasingly opaque black alloy ciliner mimicks behind the first two or three groove steps to make the rest of the barrel sorta fade into black?

[Starshina Smirnov]

zamn

[Iron Trident]

And yes, you have 100% inspired me to make my deco platform that has a myriad of barrel customization. It's still in the works.

[Iron Trident]

Ah. What I had done for my deco platform is each respective rifling I cant it maybe about a few degrees and depending on the rifling pattern I they could easily connect to one another from end to end just by inverting the direction and maybe some of the rotation to get them lined up.

[Noname117]

My only regret is not developing a technique using the triangle generator built-in to Advanced Mimic UI to smooth out the rifling. Of course, that would only be more pain, and only really doable up to 16 valleys. So I'll just stick to continuing to update my own ships and adding even more small details to make them look better for now.

[HenryWong32]

Me before reading this: Hmm I might give this a try, I've always liked messing around with mimics and decorations and I like adding tons of tiny details.

Me after reading this: Holy shit I will never do this oh my god just reading the description gave me depression turns out I'm not actually that obsessed with decorating OP you need to see a therapist

Jokes aside this is incredible. The technique is genius (but like the crazy kind of genius) and this guide is well written. The results look amazing even if they are tiny and probably invisible 90% of the time. Good job and I hope you find some way to regain your sanity after doing that.