Does anyone know if this is in any of the FFG books? (Ideally looking for official stats for DH)

Chainblade Combat Attachment. This small Chainblade is attached to

the barrel of a Space Marine Boltgun, acting as a bayonet.

I found that info here:

http://wh40k.lexicanum.com/wiki/Chainsword

I saw this - but it's for Astartes...

Otherwise I am opposed to allowing it other than a one off or special "innovative" delivery / maybe a crate's worth is all that left from a defunct manufactorum (ie Tech Heresy) - giving a good reason why this isn't being used by the Imperial Guard enmass let alone Inquisitors and their Acolytes...

Chainblade Attachment (1)

Requirements

Weapon category: Ranged

Weapon class: Basic

Weapon type: Bolt, Chain, Exotic, Flame, Grenade, Las, Launch, Luminen, Melta, Plasma, Power, Primitive, Shock, Solid Projectile, Tyranid

Modifiers

Special effect: Weapon Counts As Astares Chainsword In Close Combat

Source Deathwatch - Deathwatch Core Rulebook pg. 157

I've just checked Black Crusade. Core rulebook P169, armoury, melee attachment:

" Bayonets, chain blades, and other long bladed attachments can be fitted to most ranged weapons, making them more useful in assaults. A weapon with a melee attachment counts as a spear in close combat."

So chainblade= chains spear, powerblade= power spear, etc.

Also , DH:BoM, P120. "Sarissa

... when mounted on a bolter, a sarissa counts as an axe in close combat"

Hope this helps.

Yeah I saw that same thing too AxeSpanna in the DH2 Core Book funny enough > my player was like - just a spear?! (thinking it was garbage in comparison to a chainblade bayonet LOL)

Page 163 in the Core Book (SEE Bottom of this Email - Melee Attachment)

Melee Attachment

Upgrades: Any Basic ranged weapon

I don't like to adhoc things in > I didn't see chainspear anywhere > i think thats from the old RT days when Space Marines had beaks - which again supports the idea that chain-bayonets are for Astartes only (one could speculate the tremendous centrifical force being applied - only an Astartes scaled weapon in Astartes hands can compensate for that...

This is what I opted to do instead:

Just wanted to pop in. The "Chain Attachment" is available for any Basic weapon as listed in Only War: Hammer of the Emperor. It acts with the profile of a Chain Knife, or 1d10+1 R, Pen 2, Tearing.

OMG thank you Asymptomatic!

Checking that book now and found it - my player is gonna be really happy

Thanks Again

Stay GAMING

Morbid

Chain Attachment
Many Imperial Guard regiments are trained to affix their
standard issue combat knives to their lasguns as bayonets.
Some veteran formations and particularly well-equipped
regiments are able to mount chain-blades on their primary
weapon, allowing them to be used in close combat with
nearly the effectiveness of a chainsword, without requiring
the user to switch weapons. This extra moment can make all
the difference in desperate close-quarters combat. A weapon
with a chain attachment can be used in close combat with the
profile of a chain knife (see page 116).
Upgrades: Any Basic weapon.

I don't like to adhoc things in > I didn't see chainspear anywhere > i think thats from the old RT days when Space Marines had beaks - which again supports the idea that chain-bayonets are for Astartes only (one could speculate the tremendous centrifical force being applied - only an Astartes scaled weapon in Astartes hands can compensate for that...

I think AxeSpanna was just extrapolating. By RAW, the attachment just makes the weapon count as a spear, period -- although I can certainly see potential for a houserule respecting various special traits in the item's background, such as simply adding the Tearing trait for a chain-weapon, Power Field for power, and so on.

Note further that you shouldn't take the "spear" literal, just that the weapon would be counted as such by way of how it is wielded. The archetypical lasgun fitted with a bayonet, for example, would certainly handle like a spear in melee when you stab with it. By contrast, however, I also think that a chain attachment would handle more like an axe, like they did with the sarissa (whose massive blade is more likely to be swung like an axe or hammer simply due to the shape and weight of the weapon it is attached to, apart from its own form and mass).

Lastly, although I personally think that miniature knife-sized chainsaws are a tad silly, I certainly don't see why anyone should not be able to use them as a melee attachment. Generally, the weapons themselves should have sufficient weight/mass to compensate, and if there's stuff like this in real life, certainly it'd work just as well if you slap it onto a basic weapon such as an eight-kilo boltgun.

Anyways, I see you already found what you were looking for, so ... have fun!