Reality-testing / Playtesting the Guns Default . . .

[vicky_molokh]

Greetings, all!

So, I got the opportunity to try out just what numbers result from using Guns (Pistol) at Default, and it seems there is a discrepancy. It seems like GURPS provides results that are too harsh.

First, let's try to figure out all the numbers:

Base DX of 9 (I'm clumsier than average) and a Default skill level, so 9-4=5. IIRC Kromm said that Familiarity penalties don't stack with default penalties, so let's keep it at that.

TDMs and other modifiers:
+1 for “no risk to self” (nobody else shooting, just-serviced weapon, etc.),
+1 for “no risk to others” (all allies behind you, no risk of overpenetration or ricochet)
+1 for “no political or military stake in the outcome.”
+1 for a not-quite ideal environment (basement-like indoor, but with mediocre lighting, a sandy 'floor' etc.)
No modifier for a range that isn't precisely known (very approximately 15 metres or yards)
-1 (possibly) from poor lighting (definitely worse than a 120W bulb at 1 yard).
+2 for Acc of a Glock, possibly another +1 for an extra second (but I doubt it).
+1 for AoA.
-5 (approximately) for a Distance of about 15 yards.
-5 for shooting the target's head

Total numbers: base skill 5 plus +4 from various TDMs, +3 for Aimed AoA, and -10 for combined distance and target size, ±1 for maybe lighting and/or maybe an extra second. That gives a total modified roll against 2±1. Which means hitting should be more-or-less impossible.

Alas, I don't have precise percentages of hits, but neither I nor anybody else seemed to find this an impossible task - usually between half and all of the bullets hit. Which would require a modified skill level of perhaps 10-15. That requires somewhere between 6 and, oh, say 12 more levels of positive TDMs, which seems to be in excess of even the +10 that is provided under ideal circumstances.

(There were other firing modes and other distances, but I'm posting the one I found more memorable. I'll try to get more precise numbers later.)

Am I missing something in the rules, or is the system somewhat 'off'?

Thanks in advance!

[DouglasCole]

Originally Posted by vicky_molokh

Greetings, all!

No modifier for a range that isn't precisely known (very approximately 15 metres or yards)

Given you're trying to hit "on the paper," it seems, knowing that not only is the target basically 15 yds away but that it's not changing from shot to shot means that you definitely should get +2 or +3. This is because it's a static target not changing at all from shot to shot. You can take all of your knowledge on where the last shot hit and compensate. This is a big deal.

-1 (possibly) from poor lighting (definitely worse than a 120W bulb at 1 yard).

Were you shooting at a black-on-white or other high-contrast target?

+2 for Acc of a Glock, possibly another +1 for an extra second (but I doubt it).
+1 for AoA.

And +1 for Braced if you were using two hands.

-5 (approximately) for a Distance of about 15 yards.
-5 for shooting the target's head

Total numbers: base skill 5 plus +4 from various TDMs, +3 for Aimed AoA, and -10 for combined distance and target size, ±1 for maybe lighting and/or maybe an extra second. That gives a total modified roll against 2±1. Which means hitting should be more-or-less impossible.

The change to getting the TDM for known, invariant range and Braced, plus maybe the extra elimination of the -1 for lighting (which you include above) gives an extra +4, which means a six-inch group or so will be obtained with a skill of 6-7, maybe 6-8. That's a head shot 1/10 to 1/4 of the time.

Alas, I don't have precise percentages of hits, but neither I nor anybody else seemed to find this an impossible task - usually between half and all of the bullets hit.
Thanks in advance!

Hit the head, or hit the paper. Because given the mods above, you'd be on a man-sized target with a net skill of as much as 13.

You might also want to check out On Target and Dodge This, which both talk about shooting guns in the real-world, and On Target talks about a different way to look at Aim that might better suit what you were doing.

Personally, I've found that on-the-range TDMs tend to be in the +8 to +10 range when all is said and done. So much is known and static that in a real gunfight is not.

If you look at it that way, your base skill of 5 gets +8 to +10 from the environment, and another +4 for Acc, AoA/Braced. Less -10 for size and distance. That's positive skill and mods of 17-19, -10 for range and size, and you'd expecte to hit 15-35% of the time to the head, and you'll be "on paper," meaning in a torso-sized zone with a net skill of 12-14, which is a 75-90% hit rate. Toss in that extra second, and you're nearly always on paper, and hitting 25-50% of the time to the head.

[vicky_molokh]

Originally Posted by DouglasCole

Given you're trying to hit "on the paper," it seems, knowing that not only is the target basically 15 yds away but that it's not changing from shot to shot means that you definitely should get +2 or +3. This is because it's a static target not changing at all from shot to shot. You can take all of your knowledge on where the last shot hit and compensate. This is a big deal.

Hmm. I thought it takes a rangefinder that tells the distance down to feet before the bonus applies? But sure, maybe.

Originally Posted by DouglasCole

Were you shooting at a black-on-white or other high-contrast target?

Greyish metal against darkish . . . something, IIRC. That might compensate the lighting penalty, if any, I guess.

Originally Posted by DouglasCole

And +1 for Braced if you were using two hands.

Thanks, missed that.

Originally Posted by DouglasCole

You might also want to check out On Target and Dodge This, which both talk about shooting guns in the real-world, and On Target talks about a different way to look at Aim that might better suit what you were doing.

Oh, I was looking at the numbers in context of Basic Set / High-Tech / Tactical Shooting.


Thanks for the pointers. I'll try to get more precise numbers later and see how much better they line up with your corrections to my estimates.

[Ulzgoroth]

Originally Posted by vicky_molokh

Hmm. I thought it takes a rangefinder that tells the distance down to feet before the bonus applies? But sure, maybe.

The +3 is pretty demanding, but you can get a +1 for the target being within a yard of a known ranging point. Your 'about 15 meters' probably qualifies. (On the other hand, you shouldn't get that bonus on the first shot if you don't have the ability to use the sights to compensate for the known range. Which an untrained shooter may not.)

I don't know of any rules that actually suggest how you'd get a +2 rather than +1 or +3 for known range.

I also don't know of any rules covering this, but as DouglasCole suggests, you shouldn't really need to actually know what the range is in terms of distance units so long as you know what it is in terms of elevation adjustment for your shot. Which you can get pinned down just as well with a series of ranging shots against a stationary target as by measuring the distance and using range-calibrated adjustable sights.

Based on that I'd definitely say that after the first few iterations of firing a string of shots and checking where they landed on the target, at constant range, you should be getting the full +3 for known range even if you haven't the foggiest idea how many meters that range is.

[Daigoro]

I once shot 3 for 3 from default with a handmade crossbow aiming at a coconut about 10m away in bright sunlight.

[Tomsdad]

So what are we thinking here? +10 in non combat mods will cancel out the -10 in shot difficulty, leaving just equipment and action mods as a bonus of +4 or +5 which pretty pretty much brings us back into 50% chance of hitting territory so that seems pretty reasonable.

For me if there is a problem its with the default. It is a bit all or nothing here, i.e it's either -4 or once you paid 1cp it's removed entirely.

Now in an RPG where we're generally just interested in distinguishing between unskilled and skilled it doesn't matter. But in this RL situation the grain gets a bit finer.

FWIW I think that the -4 default probably gets reduced in smaller quicker increments (and I suspect that even if you've never fired a real pistol before we've done some kind of hand eye co-ordination thing that starts us on our way in this even if it below the granularity of 1st point in GURPS skill)

This is assuming that Vicky you've never shot a rifle or rifle like thing either, because you might be getting a slight default bump from that as well (again even if it's below GURPS granularity).

Basically the current system is not really set up to model a person's first go on a pistol range in great detail.

Another thing is I also suspect that skill improvement over time taken in RL is not the strictly linear relationship of 200/100 hours per point that is on pg293, but more in fits and starts.

(but again there's likely not much to be gained in going to into that in 99% of games)

[Tomsdad]

One quick point given you were firing at a target I'd be surprised if knowing the range didn't apply from the start, and I'm pretty sure it would apply after a couple of shots. (you'd be "zeroing" in on an immobile target) so that's a +3

Given in TS it says:

"An ideal environment
helps, giving from +1 for a typical outdoor range up to +4
for a perfectly lit indoor range."

I'd be tempted to say "+1 for a not-quite ideal environment (basement-like indoor, but with mediocre lighting, a sandy 'floor' etc.)" is a bit harsh and is double dipping with "-1 (possibly) from poor lighting (definitely worse than a 120W bulb at 1 yard)"

So where you have a net 0 I'd probably count that as maybe a +2

You used a two handed grip? if so thats braced for another +1

so I can maybe justify another +6 on top of what you've got

But even with that starting at 5 from default and then taking -10 in negative mods is the killer here

Still someone's head at 15m is a pretty good shot with no shooting experience

EDIT: or what DouglasCole said

[Edges]

Originally Posted by vicky_molokh

Greetings, all!

So, I got the opportunity to try out just what numbers result from using Guns (Pistol) at Default, and it seems there is a discrepancy. It seems like GURPS provides results that are too harsh.

First, let's try to figure out all the numbers:

Base DX of 9 (I'm clumsier than average) and a Default skill level, so 9-4=5. IIRC Kromm said that Familiarity penalties don't stack with default penalties, so let's keep it at that.

TDMs and other modifiers:
+1 for “no risk to self” (nobody else shooting, just-serviced weapon, etc.),
+1 for “no risk to others” (all allies behind you, no risk of overpenetration or ricochet)
+1 for “no political or military stake in the outcome.”
+1 for a not-quite ideal environment (basement-like indoor, but with mediocre lighting, a sandy 'floor' etc.)
No modifier for a range that isn't precisely known (very approximately 15 metres or yards)
-1 (possibly) from poor lighting (definitely worse than a 120W bulb at 1 yard).
+2 for Acc of a Glock, possibly another +1 for an extra second (but I doubt it).
+1 for AoA.
-5 (approximately) for a Distance of about 15 yards.
-5 for shooting the target's head

Total numbers: base skill 5 plus +4 from various TDMs, +3 for Aimed AoA, and -10 for combined distance and target size, ±1 for maybe lighting and/or maybe an extra second. That gives a total modified roll against 2±1. Which means hitting should be more-or-less impossible.

Alas, I don't have precise percentages of hits, but neither I nor anybody else seemed to find this an impossible task - usually between half and all of the bullets hit. Which would require a modified skill level of perhaps 10-15. That requires somewhere between 6 and, oh, say 12 more levels of positive TDMs, which seems to be in excess of even the +10 that is provided under ideal circumstances.

(There were other firing modes and other distances, but I'm posting the one I found more memorable. I'll try to get more precise numbers later.)

Am I missing something in the rules, or is the system somewhat 'off'?

Thanks in advance!

If you have the time, you might want to look at this old thread. We went over much of the same ground in some detail.

[Eukie]

GURPS does all probabilities with a 3d6 distribution, which gives a cumulative distribution of, roughly, the Gaussian Error Function.

Shooting at a circular target in the real world tends to follow more of a Rayleigh Distribution.

Since these two distributions are not the same, it'll be basically impossible to have values in GURPS that correspond to the entire range of real-world values. You might find some sweet spot where GURPS is a simulation of the real world, but GURPS isn't a good model of shooting to begin with, so your results at the gun range are partially just a result of that.

[vicky_molokh]

Regarding the 'precisely known range' bonus:
If we go by the fact that at a couple of tens of yards the trajectory is flat anyway, I'm not sure what benefit precisely-known range should provide (i.e. someone could advocate a harsh-realism houserule making the answer 'none').
But even by RAW, the Eye For Distance perk provides a 'built-in' rangefinder with an error margin of ±5%, and is considered good enough to allow Precision Aiming but not to enjoy a Rangefinder bonus. So 'approximately 15 yards or metres' is already a precision level with an even worse error margin (at least ±10%).

Regarding Defaults:
If we don't have a consensus that someone picking up a real pistol for the first time in one's life is working at Default, then the results of the reality-test become irrelevant. So I want to ask: what do you consider to be the criterion of having 0 points in a DX/Easy skill (i.e. working at an actual default while having a default)? Back when I posted my impressions with the driving default, I don't recall anyone insisting that I have a point in Driving from playing Death Track on the computer.