I know that you install it on a shoulder mount according to description, my question is up to what size weapon can you mount with a Weapon MIU I recall on the book Cadian Blood the Inquisitor I think had a psycannon with Weapon MIU on his shoulder but that is the books and not the RPG.

The devs have previously ruled that Weapon MIUs usually only carry pistol-class weapons, but in rare circumstances (possibly with a good/best quality Weapon MIU) you can mount basic weapons on it.

I see thanks, in your opinion would this then be acceptable?

Common Weapon MIU: Pistol
Good Weapon MIU: Compact Basic
Best Weapon MIU: Basic
Archeotech Weapon MIU: Heavy

Would this look acceptable and maybe not as game breaking?

You'd never, in my opinion, be able to mount a heavy weapon on your shoulder with a Weapon MIU. It's just too bulky.

Otherwise, yea, that'd work

I did allow one NPC in my game to have a heavy weapon linked - an assault cannon. Then again, Magos Durendal is a very high level Mechanicus Secutor, and is quite predictably chromed to the eyeballs. Also, he's an NPC and doesn't show up that much.

Cheers,

- V.

Since any ballistic weapon could potentially be linked to the MIU (essentially a hotswappable port wired to your brain) the weapon class of the shoulder mount shouldn't be based on quality of the unit itself (in my opinion).

Our GM ruled, rightfully so I think, that the MIU and the shoulder mount are two distinctly different devices. The shoulder mount could then hold any weapon that could conceivable be mounted on the player's shoulder (modified by their size category i.e. Hulking players can mount basic weapons as they would pistols and if they are in power armour since their size goes up again they could mount heavies).

If you are uncomfortable with them mounting basic or heavy weapons rule they can only mount custom or compact customs; increasing the difficulty and/or time required to complete the project. Besides I wouldn't expect a stock assault las to be strapped to your shoulder, but a heavily modified version removing most of the weapons bulk. The only thing that you should see is a small housing containing the essential components with a barrel sticking out of it.

I also recommend the shoulder mount be designed as a modular attachement (including the backpack ammo pack) that way it can be removed when not needed, or when customs would dictate; allowing the basic armour suit to be worn regardless. This will also allow your players to equip the pod with different configurations.

If you're the GM and you don't like any of those options it's a prime time to get creative, and write up stats for specific shoulder mounted weaponry. I would provide at least one of each type that makes sense to you and your players. I would probably draw stats from pistols since they are smaller weapons, typically do less damage, and are more likely to be the basis for shoulder mounted weapons. This might be a good way to go if you want to give/restrict access to shoulder mounted rockets and such.

Things to keep in mind weapon MIUs can be fired as a free action which means anything you can do with a ballistic weapon you can do with a MIU; however, you cannot use it in the same round you are using another attack action (one attack action per round). This limits their functionality to firing in combination with non attack actions. Moving specifically running being the most advantageous, and if you're going to fire on the run you're more likely to favor a weapon capable of semi/full auto bursts for the bonus to hit or laying down surpressing fire. The MIU is then essentially a gap closer for melee focused characters.

Another reason why they aren't typically heavy weapons is you would need the auto-stabilized trait to move and fire a shoulder mounted heavy weapon effectively, unless you house ruled it (i.e. Given the character's size for the purpose of firing heavy weapons he is considered to possess the auto-stabilized trait.) Barring that... they need to figure out some sort of rig giving them the auto-stabilized trait. Or, first brace as a half action, fire as a free action, and then move as half action. I am fairly sure bulging biceps would be of zero help in this instance since the weapon isn't being held by the character but mounted to them.

Other thoughts...

*Looks Amazed at the Scholarly Post*

Man that is some good stuff, I would then have to ask the following question how would you customize the shoulder mount. From what I understand, you are saying that it should be Weapon MIU +Weapon+Shoulder Mount System, what stats you think would be for that Shoulder Mounted System customization? Over all I like what you say as good guidelines for what to do.

I would look to the concealed weapon bionic DH:IH p138 on how a mount's quality might affect the installed weapon. Its a similar situation after all (a weapon is being broken down and custom fitted.)

"Poor: The bionic weapon functions as normal, but gains the Unreliable Quality. In addition, the weapon cannot be removed with a Disarm, and locating the weapon requires a detailed inspection or a successful auspex scan."

Here the concealed benefit only makes sense if you, or they specifically want such a mounting (compact versions only for this anything else would probably be too hard to conceal within an exterior mount.)

"Common: As Poor, but the weapon loses the Unreliable Quality."

"Good: As Common, but the weapon functions as being best craftsmanship."

This makes perfect sense to me considering the amount of work involved in fashioning a proper weapon mount. Essentially the mount and weapon become a single piece of hardware. If for whatever reason the player ever wants to remove the weapon from the mount, and use it normally it would need to be rebuilt defaulting to its original quality (but presumably you have most if not all the materials to do so; a skill check should do it).

"Disadvantage: Any catastrophic Jam or Overheat automatically disables the limb in question as well as the weapon."

The down side would be a jam or overheat would disable the weapon until it could be repaired (given its design there is no simple way of unjamming it). This really only effects mounts of common or poor quality. As Good lets the weapon function as best crafted which prevents it from ever jamming or overheating.

As for how the weapons inherent qualities affect the weapon mount I would just follow the weapon quality rules to the letter RT p115.

An unreliable weapon in a poor mount, the unreliable quality stacks and the weapon would jam on every failed roll to hit.

A reliable weapon in a poor mount, the qualities cancel each other out with the weapon possessing neither.

So on and so forth.

The only thing the book doesn't address is best quality for that i guess you have to get creative. They could gain the accurate or tearing qualities though those might be too much (essentially the weapon mount is extremely sophisticated granting some other useful bonus); it's up to you.

Good luck. I am glad others might benefit from our ideas.