The table for Hellguns says weight of backpack capacitor is separate, but there is no weight listed for it on the table the capacitor is in.

It's a question that has come up many times. I've seen the answer that it's not in fact a full backpack but a smaller one, and since hellguns weigh more than other las weapons the weight could be worked out in the normal way, which is that a full clip weighs about 10% of the weapons weight. That would make it 0.4 for a normal clip, 0.6 for a Hellgun capacitor and 1kg for D'laku capacitor.

Other than that i've noted that while the normal hellgun weighs 6kg and states that the weight is without capacitor, the d'laku weighs 10kg and does not state the same which would put it at 4 kg.

Also it talks about using normal clips and using more energy per shot, but what clip size do we go by? The value for hellpistol clip, lasgun, or one of the myriad varieties of lasgun?

Letrii said:

It says "standard lasgun charge pack" so...

Standard clip is 30 and hellpistol uses 4 per shot, so 7 shots. Would you get an 8th shot at half damage or just have 2 leftover shots for a normal laspistol?

I figure there are two ways to approach this: charge packs are universal among weapon-class or they're unique to each variant.

If the former, shot capacity is a feature of the weapon, not the charge pack. A bog-standard laspistol can eke 30 shots out of a pistol-class pack, while a Palantine can only manage 20. If you simply must swap them out, it's best to keep track of percentages and round down. A pack used to fire a standard pistol 7 times is 23% depleted - placed into a Palantine pistol, you'd have 19/25 shots left. And so on.

If the latter, that 'standard charge pack' you're putting into your hellpistol was designed specifically for the hellpistol and only provides 25% of the shots a full-size capacitor would. It costs the same, but you can't use this pack with any other pistol-type lasgun.

In either case, you end up with 5 shots (20/4). Hell-weapons have capacities in multiples of 4 to make it easy to convert.

Letrii said:

No, a standard lasgun is 60. The Las-pistol is 30. It makes little sense to load the hellgun, which is a power draining basic weapons, with pistol ammo when the bigger basic ammo packs are available.

I was talking about the hellpistol, not the hellgun in that post.

Do hellgun/pistol take the full reload time if just switching clips instead of backpack capacitors?

They didn't specify, but I'd imagine the common houserule would be to reduce it to the 1 round reload, since you're already suffering from diminished ammo capacity. And if I remember correctly, the normal capacitor has a cable that needs to be screwed-on, which is why it takes so long to reload.

Do they list weight/cost/etc for those mythical power backbacks that alot of weapons seem to use because I can't find anything aside from some bit about how non-military stuff runs power armor for 1D5 rounds.

I haven't seen them either. Trying to come up with a balanced set of armor that doesn't need external power source of no time limit on use, see my Power Armour thread in House Rules.

The cost for heavy-grade charge packs is given on the ammo table in the DH core book. There are no prices given for heavy-grade plasma, melta, or flamer ammo units, though doubling the cost of a basic unit (as they did with charge packs) would make sense. As would making them requisition-only. The '10% of the unloaded weapon' weight thing would be a good starting point (maybe go up to 20-25%), as most of the heavy weapons weigh 30-60 kilos. A 3-6 kilo backpack may seem fairly light, but energy storage technology in the Imperium is apparently pretty advanced, so it wouldn't be utterly ridiculous. And the packs are supposed to render the heavies man-portable, so the ammo can't be all that heavy, or they would only be ogryn-portable.

Aren't heavies squad support weapons? One man carries ammo and another has the weapon, or is that just the heavy flamer?

Lathi said:

On the other hand, hellguns are basic weapons and while more powerful and heavy than most normal lasguns they don't weigh nearly as much or pack anywhere near the punch of a heavy weapon. For MP-lascannons or multilasers, sure. But hellguns are closer to a normal lasgun than to an MP-lascannon both in size, weight and damage potential (i.e. power drain).

If it came up, i'd rule something like this: Name your ammo capacity preference and calculate how much that would weigh in normal charge packs, multiply by two to get the weight of your capacitor.

For example, a normal charge pack weighs 0.5 kg, we pick a capacitor that weighs 4kg and thus multiply the standard 15 shots by four to get 60 shots before reload with a hellgun or 240 for a lasgun.

I'd also allow any player willing to do the bookeeping himself to connect more than one weapon to the same backpack. No reason why you shouldn't be allowed to power your D'laku and your Aegis anabaric shock blaster from the same backpack..

For price, how about 100 thrones per kg backpack or something.