Can you aim a gun you can't see?

[Varyon]

Originally Posted by DaosusLeghki

This is not game related, but it might be worth pointing out that many guns have night-visible iron sights. This is usually done with three vials (two on the rear, one on the front) of tritium or some other glowy substance.

The authors of HT appear to have disagreed with you on the bit I bolded, as they opted to include stats for such on HT156. Collimating/Reflex sights are better, of course, and found on the same page. Either would certainly get rid of any question as to what Acc bonus you'd get for Aiming.

Originally Posted by Donny Brook

My first instinct was to say no, but this is convincing. So I'd allow Acc 1.

That sounds reasonable enough.

[Kale]

Some fiber optic sights use room light or daylight to duct light into the aiming dot so that the system doesn't need batteries and an active light source. If the gun is in darkness then the aiming dot won't be illuminated since the fiber pickup won't have any ambient light to duct into the sight system.

Note you can also aim a weapon with an under barrel flashlight by centering the circle of light around the target, which doesn't require aiming down the sights. It is sort of a poor-man's laser sight (poor in that it has a much more limited range to be effective as an aiming mechanism than a laser).

[Plane]

Originally Posted by clu2415

If your gun is invisible, then no. You have to see the iron sights, crosshairs, red dot, whatever to line it up with the target.

Conversely, stuff like Innate Attack or Spells also have an Acc which adds a bonus to hit when they take an Aim maneuver and they don't have any "sights" so to speak...

Unless perhaps we envision mages / mutants holding up their hands to use their fingers like sights? Or using the tip of a staff as a sight?

[PTTG]

Snap firing wouldn't be a problem. Actually aiming an invisible gun definitely seems difficult... though I do think you could benifit to a small degree from taking the time to line up your shot.

I would say an effective acc of no more than +1, representing the ability to effectively take a more careful, deliberate snap-shot even without looking down sights.

I agree that in the case of total darkness with an illuminated target, almost all sights will function effectively perfectly. They're usually designed with that in mind.

[vicky_molokh]

Originally Posted by Varyon

TS41 states that missing/destroyed sights drop Acc to 0; while I feel that's overly harsh, it is precedent, and I don't think it would be inappropriate for an invisible weapon. I don't have an issue allowing for Aiming, however - you can Aim with a slings and various throwing weapons, after all.

Definitely too harsh. There are many weapons with worse sighting mechanisms that have Acc 1-3: staff-slings, atlatls, old crossbows and bows, throwing axes, thrown harpoons, shuriken, blowpipes etc.

[Celjabba]

I would

-reduce the acc of an invisible weapon with build-in sight by half (round down) or to acc 3, whichever is worse

-discount any acc from separate targeting system that are invisible

-only allow adding the (reduced) acc of an invisible weapon if you are familiar with the weapon model

-the first shot on a specific target with an invisible weapon will have it's (reduced) acc capped at +1, unless you have a weapon bond

[Refplace]

Originally Posted by vicky_molokh

Definitely too harsh. There are many weapons with worse sighting mechanisms that have Acc 1-3: staff-slings, atlatls, old crossbows and bows, throwing axes, thrown harpoons, shuriken, blowpipes etc.

Note that Telescopic Sights or Telescopic Vision limit the bonus to double base ACC implying the base ACC is something other than the typical iron sights.
Also ballistics are a thing and increased ACC of modern firearms over round shot muskets should still be effective.
Of note read the section under Aiming, p. B364
Add the weapon’s Accuracy (Acc) to your skill, plus any bonuses for targeting systems used: sights, targeting computers, etc.
And later in that section...
Your combined bonus from all targeting systems (scopes, sights, computers, etc.) cannot exceed the weapon’s base Accuracy.
Also read the Sighted and Unsighted Shooting sections of GURPS Tactical Shooting.


So I'd allow base ACC but no Aiming bonus or use of sights..

[weby]

Based on own experience on the lighted target while self in dark.

In some cases you might have to roll some sort of roll to bring the weapon to shooting stance, to ready it, or to draw it. Mostly drawing and pointing a weapon in a muscle memory thing and thus "automatic" if you have done it enough. If you have familiarity penalties these rolls should definitely be rolled in that situation.

If you have red dot sight->normal situation.
If you have non night sights -> depends a bit on the actual type of sight, but you can still approximately point the weapon and might get some clue from the sights. This would definitely require a the perception roll above with penalties. But still the weapon profile and grip would give some bonuses. I would likely go with halve the total bonus from aiming and round down.
If you have night sights->It is a question of a relative brightness of the target and the night sights. It would range from above "non night sights" to a situation where your night sights are bright enough in relation to allow normal aiming.
If you have a scope->pretty close to normal situation. This would likely require a roll to get the sight picture immediately, on fail add a second to the required aim time. Once you have the target aimed, you would get the accuracy normally. Also for scopes, as they gather light, they would also help if the target is in a low light(not total darkness) situation by reducing the penalty for that.

As for invisible weapons.. Any shooting where you want to hit anything beyond couple of meters uses sights. You cannot see the sights on a invisible weapon and thus could not aim..

I believe that though that if you practiced enough with an invisible weapon you could get good enough idea based on your grip and such to qualify for aiming with acc 0(thus additional seconds of aiming give bonus).

The optimal solution would of course be to make the rest of the weapon invisible but leave sights visible getting the best of both worlds.. as the sights by themselves are so small as to be not seen by others except when something specially draws attention to them. And in any case once you take shooting stance and start aiming it is kind of obvious...

[Anaraxes]

Originally Posted by Refplace

Note that Telescopic Sights or Telescopic Vision limit the bonus to double base ACC implying the base ACC is something other than the typical iron sights.

High Tech lists the H&K PSG1, a purpose-built sniper variant of the G3A3 automatic rifle. It's relevant here because the PSG1 description notes that it deliberately omits the iron sights of the base version. The regular version has Acc 4; the PSG1 gets 6, as a Fine weapon. That Acc is actually listed as "6+2", where the +2 accounts for the scope that comes with it as standard equipment.

So, the 6 is certainly something other than a scope that also isn't the iron sights that aren't there. If +2 is for "Fine", leaving +4 for "just the barrel", then the G3A3 version isn't getting any bonus for its iron sights, either, so taking them away hardly hurts.

Certainly you could sight down a barrel with no sights and get some benefit -- and if the weapon were invisible, that's not possible. On the other hand, an expert shooter could probably do a better-than-nothing job just by holding the rifle in the grip familiar to them, just aiming it by feel. For a game cinematic enough to admit invisible weapons, I'd be tempted to make up a houserule something along the lines of using the number of CP invested in the Guns skill counted as a bonus only to cancel out the invisibility penalty, whether that's -10 or -Acc.

(The high-DX, barely-trained natural wonder doesn't benefit as much, because they don't have the kind of experience that tells you when it just feels right. And I could always use some more reasons that high-CP low-stat builds aren't dumb compared to the low-CP high-stat version of the same skill level.)

[Celjabba]

Originally Posted by weby

As for invisible weapons.. Any shooting where you want to hit anything beyond couple of meters uses sights. You cannot see the sights on a invisible weapon and thus could not aim..

While this would seem obvious,
there is the fact that throwing weapons, innate attacks, staff sling and various other ranged weapon can be aimed and get bonus acc without sights of any kind.

You can aim with a throwing axe, I would guess you could do so even if it was invisible, so why not with a rifle ?

The question is, what kind of acc penalty do you get if the weapon innate targeting help (sight, ...) are invisible.

Tactical shooting seem to say "zero acc if no sight" but that seem harsh.
If I have an invisible blunderbuss and an invisible sniper rifle, I would guess I am more likely to hit a target (after a zeroing shot or two) with the sniper rifle.

Add-on targeting help are off (except for a laser pointer, I imagine), but what part of the +acc from a rifle is the innate accuracy, and what part is the built-in sight ?