Thursday, May 3, 2018

Ultra-Tech Ultra-Gear: 30mm Gyroc

Who doesn't like the idea of arming themselves with hand held rocket launchers?

While Ultra-Tech gave some us some 15mm gyrocs to play with, I think it doesn't hurt to up the firepower quota a little higher.

In todays post I not only give a 4th edition take on 30mm gyrocs, but stat every type of warhead a 30mm warhead can take as well as give you guys some more upgrade options for both 15 and 30mm gyrocs.

Follow me after the jump if you are read to Gy-Roc!

Welp, looks like TL9 is getting closer and closer.
See pages 144-145 of Ultra-Tech for the rules covering gyroc weapons.

30mm Gyroc Weapons (TL9)
30mm gyrocs follow all the same basic rules as their smaller 15mm kin. Their larger size is both their high and low point. The have double the penetration and can carry explosive warheads that are eight times heavier but almost weigh a pound a pop and are quite large being almost three inches long. This puts a hard limit on how many rounds that can be carried, not only because of weight but do to their bulk.

Do to this they do not lend themselves to quite as versatile a range of weapons as 15mm gyrocs do and the launch platforms for them start to resemble more traditional rocket launchers then the more gun like designs of the smaller round.

Below are few possible man portable or semi-portable designs. In general these would be seen more as a light vehicle mounted system.

Gyroc Carbine, 30mm: A rifle-form 30mm semi-automatic rocket-grenade launcher.

Assault Gyroc Laucher, 30mm: A fully automatic 30mm gyroc launcher. Too heavy for normal soldiers to use, it is often either mounted on vehicular pintle mounts or by battlesuited troopers. If used mounted its ST becomes 15M.

Gyroc Pistol, 30mm: A massive 3 chambered 30mm gyroc revolver. While is has seen limited military use, it has been popular with police forces an less then lethal platform for riot control as well as for wealthy gun enthusiasts as a "fun" gun to shoot on the range.

 Break Action Gyroc, 30mm: A single shot 30mm gyroc launcher that resembles a more modern, pistol form version of the old M79 thump gun.

Underbarrel Gyroc, 30mm: An upscaled version of the 15mm underbarrel gyroc launcher that is used when heavier firepower is needed. Use the Bulk, ST, and sighting bonuses of the weapon it is installed in.

Net Fire Gyroc System, 30mm[1]: A portable or vehicle multiple gyroc launch system that is essentially a rocket powered mortar system. It resembles a mini VLS (vertical launch system) and is generally referred to as a "missile in a box".

Gyroc Launcher Table

GUNS (GYROC) (DX-4, or most other Guns at -4)
TL Weapon                                        Damage     Acc    Range    Weight   RoF   Shots   ST   Bulk   Rcl    Cost          LC Notes
9   Gyroc Carbine, 30mm                  12d pi++    2        1,900      11/4.4    3        5(3)     7†   -5        1        $2,200/$35   2
9  Assault Gyroc Laucher, 30mm      12d pi++    2       1,900       41/13    6       15(5)   11†  -10       1        $9,400/$75   1
9  Gyroc Pistol, 30mm                      12d pi++     1       1,900       6/2.4     3        3(3i)     9     -2       1        $1,200           3
9  Break Action Gyroc, 30mm          12d pi++     2       1,900      2/0.8     1         1(3)     7      -2       1       $400               3
9 Underbarrel Gyroc, 30mm             12d pi++     2       1,900      6.5/2.6  3         3(3)     7†     -        1       $730/$27        2  [1]
9 Net Fire Launch System, 30mm     12d pi++     2       1,900     19.2/9.6  12     12(3i)  9M   -7       1      $1,440             2
[1] May be attached to any weapon of Bulk -4 to -6; use that weapon’s Bulk.

 TL Weapon                                       Damage     Acc    Range    Weight   RoF   Shots   ST   Bulk   Rcl    Cost         LC Notes
 9 Net Fire Launch System, 30mm[1]    12d pi++     2       1,900     19.2/9.6  12     12(3i)  9M      -7       1      $1,440       2

Gyroc Ammunition Table
TL  Ammo                      WPS    CPS    LC
9     30mm gyroc             0.8       $40      3
9     30mm minimissile   0.8       $160    3

Gyroc Upgrades
The following upgrades are available for either 15 or 30mm gyrocs.

Velocity Option

High Velocity: 15mm and 30mm gyrocs are available in high velocity versions. These cost the same but trade increased kinetic impact for a greatly reduced range. Range for both types ranges drop to 500 yards but damage increases to 15d pi++ for a 15mm gyrocs and to 6d×5 pi++ for 30mm gyrocs.

Guidance Options
While not as capable of adding an IR homing system, these guidance systems offer more adorable options to increase the chance to hit with a gyroc system.

Laser-Homing: Adds +3 to the gyroc accuracy when making a GUNS (GYROC) roll but requires a target to be lased by a laser sight or designator. Ineffective if the target is covered by smoke, heavy fog, etc. Double the rounds cost.

Nano-Optic Guidance: Adds an nano-optic array to the gyroc with advanced optical tracking capability. Increases a gyrocs Acc by +3 when fired using GUNS (GYROC) after taking an Aim Maneuver. Triple the rounds cost.

Higher Tech Level Options 
Now TL9 gyrocs are fine and all, what if you want to use them in a higher TL game?

Well ask no farther!

Below covers the improvements that higher tech levels bring to gyrocs. Under damage the figure before the dash is for 15mm gyrocs while the number after the dash is for 30mm gyrocs.

Gyrocs at Higher Tech Levels
TL             Damage                        Range
10             9d pi++/18d pi++         2,900
11            12 pi++/24d pi++          3,800
12           18d pi++/ 36 pi++          5,700

If you use the High Velocity option for higher TL rounds, multiply damage by ×2.5 and range by ×0.26.

30mm Warheads
Now that you got a 30mm gyrocs to play with, might as well throw in some warhead options to top things off.

Below you will find the stats for every type of of warhead that a 30mm warhead can use (expect for ones that just slap a armor divisor like APHC and so on). See Ultra-Tech pg. 152-159 for the full rules on all the listed warhead options.

30mm Warhead Ammunition Table
TL  Ammo                      WPS    CPS    LC
9    30mm  warhead        0.05     $1        3

Note: I found that the formula I used for figuring the dose size for Biochemical Aerosol and Liquid  rounds in my Warheads R Us post are off for smaller rounds. While I found a stop gap that works sorta, it's not 100% yet. I'll update that post as soon as I figure out something that works for all warhead sizes (assuming their is an actual solution).

Warhead             Damage
30mm                1d+1 cr ex[1d+2]

Biochemical Aerosol
Warhead     Damage                Dose
30mm         spec. (3 yard)           16

Biochemical Liquid
Warhead   Damage               Dose
30mm      spec. (3 yards)          7

Warhead    Damage
30mm        spec. (300 yards)

High Explosive (HE)
Warhead   Damage
30mm       5d cr ex [1d+2]

High Explosive Concussive (HEC)
Warhead   Damage
30mm       5d cr ex

Shaped Charge
Warhead   Damage
30mm       6d×3(10) cr inc + linked 2d+2 cr ex [1d+2]

Smart Explosively Forged Projectile (SEFOP)
Warhead   Damage
30mm       6d×3(3)

Warhead    Damage
30mm        ST 18 (+1 per additional layer)

Warhead         Damage
30mm            10d cr ex inc

High Explosive Multi-Purpose (HEMP)
Note: This warhead is TL10+.
Warhead         Damage
30mm            7d×3(10) cr inc + linked 2d+2 cr ex [1d+2] 

Note: This warhead it TL10+.
Warhead    Damage
30mm       1d+2 burn sur

Note: This warhead is TL12+.
Warhead             Damage
0.017 kiloton      6d×260 cr ex
linked                 6d×240 burn ex* rad sur
0.17                    6d×830 cr ex
linked                 6d×770 burn ex* rad sur
1.7 kiloton         6d×2,600 cr ex
linked                6d×2,400 burn ex* rad sur
* Divided by distance from the blast center, rather than by 3× distance.

Anti-Matter Warhead
Note: This warhead is TL12+. This warhead can take any anti-matter warhead size up to the one listed below.
Warhead                      Damage
27 micrograms             6d×60 burn ex* sur
linked                           6d×5,000,000  tox rad†
* Divided by distance from the blast center, rather than by 3× distance.
† Divided by square of the distance.

Warhead   Damage
30mm       spec. (3 yards) + 1d-1 cr ex

Expendable Jammer
Warhead           Damage
30mm               30 yard radius

Warhead    Damage
30mm        HT-3 aff (3 yard radius)

Warhead    Damage
30mm        HT-3 aff (3 yard radius)

Note: This warhead is TL10^+.
Warhead    Damage
30mm        5d+1 cr dkb ex

Note: This warhead is TL10^+.
Warhead    Damage
30mm        5d×10 burn ex sur

Note: This warhead is TL12^+.
Warhead    Damage
30mm         spec. (3 yards)

Alrighty guys, I hope you have fun with you new toy! Just to remember to blow up the bad guys responsibly.

[1]Forgot to make the Net Fire System use the Artillery skill. It's more of a mortar system in how its used then a direct fire weapon rocket system. 



  1. Nice, I was really stuck in a gyroc pickle and this article had just about what I needed.

    One question though: Why define a wholly new caliber instead of sticking to regular Ultra-Tech ones like 25mm or 40mm?

    1. Always glad to help!

      As to why for I do what I did, it was basically do to three reasons.

      1)I've figured out how Ultra-Tech scales warheads (they're basically the same as the warhead scale used in Transhuman Space) and went, hey why not heh.

      2)30mm Gyrcos were a thing in 3rd edition and Transhuman Space so it just kinda made sense to me to bring em into 4th edition.

      3)It's just a matter of giving players more options. 30mm is a pretty common caliber so I can see some players having a need it.

      That and I guess a 4th reason would be I enjoy having to warp me head around figuring out, "How do I do this?". It just would of been too easy to stat up a 25mm gyroc to be fun heh.

      Also now that I think about it I should probably make the net fire box use the Artillery (Cannon) skill since it's fired more like a mortar.

  2. Given you multiplied damage linearly with caliber, it should be easy to make even stranger caliber Gyrocs from here as well.

    2,7mm gyric-kolibri anyone?

    1. Damage scales roughly with caliber only if the velocity stays the same and the weight follows the difference in caliber cube. Make the gyroc lighter or heavier or faster or slower and the damage changes.

      I should also note that I rounded the numbers off a bit to better fit.

  3. Thanks for this, I think the gyroc is a weapon that doesn't get enough love compared to other weapons around that TL. The main place I've used them in a game (and we never did end up using them on that mission but we had them along in case) was a mission in microgravity.

    Other calibers I could see people wanting to use to emulate some kinds of games would be 19 mm aka .75 inch for the standard 40K Bolter, and 25mm or aprox 1 inch for the Heavy Bolter. Though those are a bit weirder as they seem to use a standard cased charged to get the projectile started and then let the rocket take over.

    I expect to emulate those it's a heavier round, notable recoil, but also no minimum damage range (i.e. the way gyrocs do less damage at short range before they get up to speed).

    Why you would want to do this is left as an exercise for the reader, though it's probably just 'model makers and artists keep assuming guns should fire shell casings around'.


    1. You’re welcome heh.

      Yeah, gyrocompass did just seem like they were just shoe-horned into the book. They just didn’t have enough options and the 15mm round doesn’t have enough punch at TL9.

      The 30mm gyroc solves some of these problems and also gives you guys a new warhead size to play with to boot.

      Ah the Bolter. There’s also the .50 cal. version used by the sisters of battle and hive under gangers heh. Which oddly has the same stats as the full sized Bolter.

      I’ve been trying to figure out how best to handle them but yeaahhhh...

      Now if it made sense as just a rocket boosted round it wouldn’t be that bad. It would be as simple as building the round as normal and strapping a rocket to it, these actually exist (though usually only as navel artillery IRL).

      Though since Space Marines are a close combat force it doesn't make sense for them to use a weapon that is less powerful at close range!

      So how that I see it is that the rocket is a two step device. The first step is a pulse detonation device which basically instantly accelerates the round to max velocity. The second step would be a sustainor motor that just fires enough to counter drag. This is of course a far more complex method but one that makes sense.

      So yeah, more quadratic formulation for me, yaaay.