Problem with full pellets shotgun damage [4th]

[giomvrck]

Hello. My name is Adriel (and my wife Giovana). This is our first post. We have a doubt and we would like that someone explain something to us. First of all, let me show what we have understood of the rule. On Basic Set we get shotguns with a RoF "a"x"b", which "a" means the number of shots per turn and "b" the number of pellets on each shot. Ok, so we get +5 to effective skill due to Rapid Fire rules, if shot all the 3 shots on a turn, and the number of pellets we hit is determined by the Rcl "1" like any other Rapid Fire gun attacks. So the damage is 1d+1 for each pellet. If a shotgun is fired within 10% of its 1/2D the damage is 1d+1 times half the number of pellets per shot (rounded down), or 4d+4. The problem we've noticed is (which is our doubt) that this close range hit (that you are hiting all the nine pellets) is less than 9d+9 gotten from hit all the pellets if shooting a target out of 10% of 1/2D of the shotgun. So the doubt is: why you hit ALL the nine pellets in a very close range and get only half maximum pellets damage per shot? High-tech book says that since the pellets are spreading, you probally will miss most of it in a more far shot. But if you hit, the damage is 9d+9. Here a example where we show this in practice: Supose that my character has Guns/TL8 (Shotgun)-25 (say, he is a true master on it), and shots a target at 25 yards apart - far enough to the pellets to spread) - he will have 25-7 from range getting a 18. If he shot one bullet he will get +1 from Rapid Fire raising to 19. Using All-out Attack (Determined) he will get +1 for a total of 20. He shots and get a 11 on 3d, which means he hits all the nine pellets, for a 9d+9 (1d+1 from each pellet) of damage. But if he was at 2 yards of his target he will get only one hit of 4d+4 (hiting all the same 9 pellets). So, we dont understand this, we miss something on the rules? Or its a flaw in the system? Someone can explain it to us? We will be very glad. Note: sorry if my english is bad, we are Brazilian and we not consider us fluent in English. The example above is valid for other skill levels and more closer distances.

[MrFix]

4d+4 is the average damage of 4/9 pellets hitting. It is there to ensure that a person who shotguns somebody at 2 yards and only barely succeeds does not lose all of his 8 pellets to the void, which would be silly.

If you have extreme SLs, or are comfortable with somebody who has shotgun-10 doing a houdini on his ammunition, feel free not to use this rule.

[giomvrck]

We understood your reasoning. We dont have problems with this rule, we only dont have understood the incongruence we've shown. So we have decided to consider the higher damage. If shooting beyond 10% of 1/2D we consider normal pellet hits (1 to 9 - if firing one shot). But within 10% of 1/2D we take the higher. If a shootist gets 3 pellets only, we consider the average (9/2 = 4 * 1d+1 = 4d+4). This is because the pellets dont spread too much, which is EXACTLY what the rule says. But if the same shootist gets 5 pellets or more, we consider the higher hit (5 to 9 pellets). This is very fine for us. Thank you very much for the answer, it was very important and clarifying.

[Ulzgoroth]

Recommend throwing in some paragraph breaks. The wall-of-text effect makes things harder to read!

Anyway, what you've found is probably a bug - and there's a fix to be found in a later book. It's two high-impact changes actually.

The first one, which fixes the loss of damage you're noticing, is switching the damage type of the close-range shot blast to pi++. That makes the wounding from the big hit be almost the same as hitting with all pellets.

However, there's a downside that goes with that. Because each shot at close range is a whole shot shell, not a single buckshot, you shouldn't use rcl 1. Instead, you should use the rcl value for slugs. If you don't know what that value is (that stat was introduced in High Tech I think), it's most often 5.

[Donny Brook]

Note that 1D+1 nine times is not the same as 9D+9.

The target's DR applies to each 1D+1 individually.

[giomvrck]

We know Donny Brook. When we told about multiplied damage like those 9d+9 we have presumed multiple pellet damage and not a whole solid bullet, which in this case would be slugs. And presuming that induces the rule of individual pellet penetration in armor/covers. Thank you for bring it to here. Some readers may not understand our presuptiom.

We are analysing your point, Ulzgoroth. Theres a problem in using slug Rcl when firing buckshot, even at very clos range. Mainly because the way of Rapid Fire and bucks of pellets interacts itself. As for multiplying damage (using pi++ like slugs) its seems to be reasonable, but the problems is that, like we know, each damage are seperated, because the shot is a load of pellets, so it needs to penetrate armor individualy, even at the very close range we are talking about.

[Ulzgoroth]

Originally Posted by giomvrck

We are analysing your point, Ulzgoroth. Theres a problem in using slug Rcl when firing buckshot, even at very clos range. Mainly because the way of Rapid Fire and bucks of pellets interacts itself.

I don't know what problem you're seeing, but the close range rules remove the rapid fire effects of the pellets, so those effects are not going to be interacting with anything.

Originally Posted by giomvrck

As for multiplying damage (using pi++ like slugs) its seems to be reasonable, but the problems is that, like we know, each damage are seperated, because the shot is a load of pellets, so it needs to penetrate armor individualy, even at the very close range we are talking about.

That's covered by multiplying the target's DR, as seen in the Basic Set. Changing the wounding modifier is irrelevant to armor penetration.

[giomvrck]

Originally Posted by Ulzgoroth

I don't know what problem you're seeing, but the close range rules remove the rapid fire effects of the pellets, so those effects are not going to be interacting with anything.

Oh, we understood now, we was forgeting the fact that RoF is not used in very close range shots. Which makes sense, actually. So in this case your solution sounds good.

Originally Posted by Ulzgoroth

That's covered by multiplying the target's DR, as seen in the Basic Set. Changing the wounding modifier is irrelevant to armor penetration.

As for it, we are having problem to figure out why this wound modfier should be applied, since the shot continues to be a load of separated pellets and not a huge solid projectile (which in the case of slugs, for gurps, means pi++). We just get to figure out the idea of using full pellet damage (9d+9 instead of those 4d+4 the rule says). Can you explain it to us? Thanks.

[giomvrck]

Wait. Is using slug Rcl when firing buckshot at very close range actually reasonable? We asks this because we believe (but not sure) that loads of pellets uses less gunpowder than a single heavy-weight solid bullet like a rifled slug, so this is why GURPS treats Rcl 1 (but mainly because the Rapid Fire, though).

[Tomsdad]

Originally Posted by giomvrck

Wait. Is using slug Rcl when firing buckshot at very close range actually reasonable? We asks this because we believe (but not sure) that loads of pellets uses less gunpowder than a single heavy-weight solid bullet like a rifled slug, so this is why GURPS treats Rcl 1 (but mainly because the Rapid Fire, though).

Short answer

It's as you say the Rapid fire Rcl rules for shotguns.





Long answer

Ultimately GURPS treats shotguns firing shot and shotguns firing slugs differently. But shot rules also change again between very close range and longer ranges, and sometimes not all the related stats adjust for that (Rcl being one, but this is fixed in Tactical shooting).

In Real life propellant loads can vary not just for different types of projectile loads in the same shell but for the same type of projectile load in different shell. but I think GURPS default is that for simplicity they are the same unless it specially refers to it in a specific weapon's listing or projectile option.

For instance there are writes up for longer "magnum" shells available and usable for some shotguns with extra capacity to allow for more propellant that increases base damage for both Slug and shot

"Extra powerful" is a general option for rounds for guns in general


Some guns have listings for more or less powerful rounds being available for them e.g some revolvers (but not exclusively revolvers)


Tactical shooting makes the point that at TL8 improved propellant in shot shells allows less propellant so more room for more projectiles to mean more projectiles at propelled at the same force in the same size shell. (this is in addition to the larger shells options above)


If you have High Tech it goes into converting between a single projectile (e.g a shotgun slug) and multiple projectiles (e.g shot gun shot) and the assumption seems to be the projecting force is the same.

In real life there is obviously reasons for reducing propellant loads in different situations, but GURPS because it's mainly looking at combat tends to assume people are either firing slugs or 000 at each other as hard as they can (or even harder if the options allow).


However a simple way to express a less powerful propellant load would be just to reverse the Extra Powerful calculation in High tech.

But not all these options actually adjust the Rcl stat! The Rcl stat in GURPS is a mix of different real world things not just the backwards force of propellant charge going off! And on top of that isn't very granular so can be hard to adjust for small differences.

Ultimately if you want to reduce the Slug Rcl by 1 on some shotguns because you think they are using less propellant when firing Shot and that should express in terms of GURPS Rcl and needing less successes to get more hits go for it! Firing shotshells at very close range at rcl 4 instead of 5 isn't likely to break your game .