When I wrote the post on making snap decisions under fire, I touched on aiming a bit, as well as tracking targets.
I’m going to revisit that a bit, somewhat inspired by this thread, but not entirely. I’m going to be speaking qualitatively here, since some of the ideas kicking around in my head might well be nice as actual rules.
The way I see it (and have done it, so I’m not just making stuff up here), as you try and draw a bead on a target, you’re going to need to consider a few things.
The first, and most obvious, thing you need is to be able to see what you’re shooting at. This will be some sort of modified Perception roll. The usual is Per+10 if the target is in plain sight, less range, lighting, and camouflage or stealth (or both) factored in. If you can see the target, you might want to shoot it. However, in order to do that . . .
Line it up
While this is usefully abstracted into a Guns roll in vanilla GURPS, as you aim, you first have to ensure that your sights (or scope!) and your target are more or less lined up. That is, you need a sight picture so that you might deliver your shots more or less where you think.
Hans-Christian Vortisch does a nice job of describing what happens when you shoot without such a sight picture in his section on Unsighted Shooting (GURPS Tactical Shooting, p. 13). You don’t even need to see the sights or gun; just go with where you feel is the right place to shoot, and pull the trigger. This is far, far more accurate (or can be) than it sounds, with practice. You still have to see your target, of course.
If you’re lining up the sights or using a scope, you need to get the sight picture aligned with the target. This is the first part, but not the only part, of Aiming. Once you do that – and in GURPS, that happens automatically as soon as you declare an Aim maneuver – you can either shoot, or try and dial in your shot a bit more.
Now, in GURPS, you have two choices. Well, one, really. You can continue to Aim for another few seconds, after which your Acc tops out at +Acc+2 and that’s it, or you can invoke Precision Aiming (Tactical Shooting, p. 26) to increase that to up to +Acc+7 by taking a series of difficult (IQ-based) Guns rolls. Fail and you have to start over, and it takes more than a minute (90 turns!) to claim the largest bonus.
Now, in reality, to get that large a bonus, especially at distance, you had best know the ballistics of your weapon as well as the target’s range. Even so, the “Minute of Angle” rule should apply, which caps the maximum effective skill before range, speed, and size modifiers are assessed, at 22+2*Acc, and that’s the base Acc of the weapon (match-grade ammo and quality weaponry increases Acc; I quibbled with this in the playtest a bit).
Scoping it Out.
One of the interesting things to deal with in GURPS are telescopic sights, also known as scopes. GURPS gives you a +1 for each x2 multiplication in range. So a x2 scope gives +1, a x8 scope gives +3, etc.
Variable scopes can be dialed in, and it’s always been a bit weird how that’s figured – why not always use the maximum bonus?
|FoV Width (yards)
The one rules nugget I’ll toss in here is a different way of looking at scopes. Simply treat the magnification as what it is – something that makes the target larger. Look up the magnification on p. B550. Yes, that’s the Size and Speed/Range Table, and just remember, that in GURPS, if the answer isn’t “consult the Size and Speed/Range Table,” you’re probably asking the wrong question.
Anyway, look it up, consult the Size table, and add 2. Use the smaller number if you have to pick. There is no x4 entry (you choose between 3 and 5), so you choose 3 and you get a +4 bonus. A 30x scope is +9.
That’s a much larger bonus than usual, but what it basically does is says “hey, you’ve just made your 6′ tall target effectively 24′ tall,” and treating that as a linear increase in size – that is, you’ve effectively increased the SM of your target, and you get a commensurate bonus.
However, and there’s always a however, a scope restricts your arc of vision. In GURPS, you can see pretty much anywhere in your front 180 degree arc. At 100 yards, that’s effectively a 314-yard field of view wide (the half-circle in front of you). A typical 3x riflescope might restrict that down to 30-ish feet, and a 9x is about 14 feet. So says this website, anyway.
So if we do some funky math (and honestly, I’m curve-fitting because I have no desire to actually derive this, and it seems more complicated than what I thought) we might say that through a scope, your field of view, even for a 1x scope, is restricted to 20 yards wide at 100 yard range. A 10x scope is only 4 yards wide.
What does all this crap mean?
Basically, it should probably take time to find your quarry through a scope. The higher the magnification, the narrower your field of view, and the more you probably have to search for it. Novices can wave their guns around quite a bit.
Red dot type sights (usually not scopes, but you can get magnifying objectives for them in the 3-4x range) keep field of view, which is cool, but don’t usually magnify, meaning you suffer full range/size penalties for what you’re shooting at.
How would I attempt to resolve it? Well, +Peter V. Dell’Orto will mock me, but it will be more die rolls.
First, you need to find your target. This would be a Per roll with naked eyes, using the usual rules.
Then, you need to get a sight picture. I would probably do something like a Per-based Guns roll, with a penalty for field of view and the Bulk of the firearm.
Once you get that, I’d probably make the shooter make a DX-based Guns roll to position the sights on target. Margin of success would determine the Acc bonus. Roll well, you get a big boost. Roll poorly, and you might even loose the target and have to re-acquire.
I like having PCs roll dice. I think it’s more fun for the player to invoke skill (via the Guns roll). I think making Aim effectively an attack roll, which can be done quickly with Rapid Strike, which would require All-Out Attack (Determined) to claim certain bonuses, and which potentially could get a perfect sight picture in a moment, or spend several seconds and not get much of anything, feels a bit more real to me. You could also perhaps have scopes, sights, etc. only cancel out range and target size penalties. It does need to be worked out – GURPS has a lot of detail with respect to firearms, and you’d need something that replaces the “you get your Acc bonus to your skill” with a satisfying mechanic that gives more or less the same realistic results we get with the current system, but has variability in how long it takes to get that target fixed.
And if I’ve been unusually vague on this one, well, I’ve not worked out the math and mechanics fully, and who knows . . . maybe it’ll show up in Pyramid one day.