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Old 11-29-2008, 01:23 PM   #1
Jovus
 
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Default Alternate Rapid Fire rules

I was dissatisfied with the Rapid Fire rules given in the Basic Set, because, as has been discussed, they terribly marginalize high-RoF weapons. Here is my homebrew variant:

The magic number is 5. Keep that in mind.

Multiply the weapon's Recoil statistic by five. This number is the amount the shooter must make his roll by in order to hit with "all" of the bullets. Conversely, each +1 in the range of success needed to hit with "all" indicates a certain number of bullets. However, many RoFs are not multiples of Recoil*5. In cases like this, round up to the nearest RoF that is a multiple of Recoil*5, and treat the weapon as though it has that A pair of examples:

GI Joe is firing his M4A1. It has an RoF of 15, and a Recoil of 2. Since the Recoil is 2, he needs a success by +10 to hit with "all" of the bullets. For purposes of this rule, the RoF is considered 20, meaning that for each point he makes his skill roll by, 2 bullets hit the target, until he runs out of bullets. His Guns(Rifle) skill is an effective level 13, and he rolls a 7, making it by +6. Twelve bullets hit.

Bruno is firing a Minigun with RoF 66 and a Recoil of 2. Since the recoil is 2, he needs a success by +10 to hit with "all" of the bullets. For purposes of this rule, RoF is considered 70, meaning that for each point he makes his skill roll by, 7 bullets the target, until he runs out of bullets. His Gunner(Machine Gun) skill is an effective level 20, and he rolls an 11, making it by +9. Sixty-three bullets hit.

Finally, using this rule with more sane RoFs behaves exactly as in the Basic Set, as shown below.

Sam Spade is firing his .38 Special with RoF 3 and a recoil of 1. Since the recoil is 1, he needs success by +5 to hit with "all" of the bullets. For purposes of this rule, RoF is considered 5, meaning that for each point he makes his skill role by, 1 bullet hits. His Guns(Pistol) skill is effective level 12, and he rolls a 9, making it by +3. Three bullets hit. Had he made it by +4, still only three bullets would have hit, because he only fired three.

Generally, with an RoF less than 5, you don't need to worry about doing it this alternate way.

A few things of note: going from +9 to +10 results in fewer extra hits than any other interval. This is from rounding the RoF up as shown above. If you wanted, you could do precise calculation with the exact RoF, but I found that too cumbersome during play (unless you can do decimal multiplication in your head as quickly as you can speak). You might also choose to round off the RoF instead of rounding up, requiring a success by another +1 to hit with the extras, but that's a little more calculation as well.

Why'd I choose 5 as the magic number? Gut feeling. Feel free to change it however you please, but I wouldn't go lower than 4, or higher than 6. Furthermore, multiplication by 5 is easy. Finally, it scales nicely with the old idea of a critical hit giving you a hit with all of the bullets, in cases where Recoil is 2 (the majority of high-RoF weaponry).
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Old 11-29-2008, 01:51 PM   #2
dynaman
 
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Default Re: Alternate Rapid Fire rules

Another possible option, instead of adding 1 to hit for each higher ROF allow the shooter to subtract one from Recoil (and if the recoil is at 1 or below halve it instead). This would indicate the shooter is trying to keep the shot pattern tight in an attempt to score multiple hits, rather then spreading them out in the attempt to get a single hit.

So a recoil 2 weapon would work like follows.

ROF 5: +1 to hit or recoil is 1
ROF 9: +2 to hit or recoil is .5
ROF 13: +3 to hit or recoil is .25 (1/4)
ROF 17: +4 to hit or recoil is 1/8
etc...


I would also allow splitting them, so the shooter could choose +1 to hit and .5 recoil instead of +3 to hit...
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Old 11-29-2008, 02:02 PM   #3
Dinadon
 
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Default Re: Alternate Rapid Fire rules

Quote:
Originally Posted by dynaman
Another possible option, instead of adding 1 to hit for each higher ROF allow the shooter to subtract one from Recoil (and if the recoil is at 1 or below halve it instead). This would indicate the shooter is trying to keep the shot pattern tight in an attempt to score multiple hits, rather then spreading them out in the attempt to get a single hit.
Yonk.
An interesting idea, I personally wouldn't halve it, but instead would have the +1 either apply to the the Hit roll or increase the number of shots that hit for every multiple of the recoil you succed by, so for a recoil 2 weapon:

RoF 5: +1 to hit or hit with 2 shots per 2 margin of success
RoF 9: +2 to hit, or hit with 3 shots per 2 margin of success
RoF 13: +3 to hit, or hit with 4 shots per 2 margin of success
etc.
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Old 11-30-2008, 02:13 AM   #4
vicky_molokh
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Default Re: Alternate Rapid Fire rules

I've always thought that 10% shots per MoS multiple equal to Rcl was the quickest fix. But if we want to change it fully, weapons should have a listed number of hits per 1 MoS (which can be a fractional number, in which case the end value is rownded down, minimum one).
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Old 11-30-2008, 02:39 AM   #5
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Default Re: Alternate Rapid Fire rules

Something I've found myself wondering is why Gurps doesn't regularly give a bonus to hit for 2+ shots. My understanding is that firing twice or firing a 3-round burst greatly increases the chances that a bullet will hit.

There are two ways I've thought around this - either the increased chances to hit from firing twice come from taking two attack actions, or the table under-represents the benefits of rapid fire. At the moment, I tend to think the latter - it seems like some training dictates that you should fire two shots basically automatically, as though it's one attack, and rifles that fire 3-round bursts do so with one trigger pull.

In this case, I'd suggest a revised table:

1: +0
2-4: +1
5-8: +2
9-12: +3
13-16: +4
17-24: +5
25-49: +6
etc...

Basically, just add +1 the regular rapid-fire table.

As far as things go with super-high rof weapons not landing enough shots... I can understand why someone might want to increase the number of shots landed, but I think it might impede playability. Besides, realistically, the bullets will be travelling out in a cone, and beyond a certain range for a target of a given size, the beaten zone will be larger than the target, so it will be impossible for all of your shots to hit. Trying to realistically figure that out might get overly complicated.

There might be an easy way to treat super-high-rof attacks like shotguns or cone-attacks or something, but I'm not sure how effective it would be.
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Old 11-30-2008, 03:28 AM   #6
Dinadon
 
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Default Re: Alternate Rapid Fire rules

Quote:
Originally Posted by elustran
Something I've found myself wondering is why Gurps doesn't regularly give a bonus to hit for 2+ shots. My understanding is that firing twice or firing a 3-round burst greatly increases the chances that a bullet will hit.
No point. Most gunmen should be able to pass by a margin of one or two, so for most RoF 2-4 weapons you should expect to hit with most (if not all shots) without any need for a +1.

One thing, how would these alternatives interact with the rules for dodging rapid fire?
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Old 11-30-2008, 11:05 AM   #7
DouglasCole
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Default Re: Alternate Rapid Fire rules

Quote:
Originally Posted by elustran
At the moment, I tend to think the latter - it seems like some training dictates that you should fire two shots basically automatically, as though it's one attack, and rifles that fire 3-round bursts do so with one trigger pull.

In this case, I'd suggest a revised table:
I toyed with, mentally, a doubling table:

Bullets Acc Bonus
1-2 0
3-4 +1
5-8 +2
9-16 +3
17-32 +4
...etc

Strictly, it should be +1 for two bullets, +2 for 3-4, etc. But two shots has benefits of their own, and hitting with both is quite possible without much fuss. The Rcl reduction you get for a high-cyclic controlled 2-round burst more than makes up for the lack of Acc. Three or four round bursts seem typical and about equal in the benefits, and +2 (effectively doubling the range at which you can expect to hit) seems pushing it too much.
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Old 11-30-2008, 01:36 PM   #8
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Default Re: Alternate Rapid Fire rules

Quote:
Originally Posted by DouglasCole
I toyed with, mentally, a doubling table:

Bullets Acc Bonus
1-2 0
3-4 +1
5-8 +2
9-16 +3
17-32 +4
...etc
I tried to recalculate a Rapid Fire table some time ago, basing it on angles and probabilistic distribution over an area. I can't remember what I ended up with, but the most significant change was with 2-4 bullets where I got +1, but your reasons for restricting this to 3-4 bullets makes sense.
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Old 11-30-2008, 08:49 PM   #9
dynaman
 
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Default Re: Alternate Rapid Fire rules

In my own games I've simply made the +1 start at 3 rounds rather then 5, leaving the rest of the table as is.
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Old 12-01-2008, 04:32 AM   #10
Ultraviolet
 
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Default Re: Alternate Rapid Fire rules

I actually like the Rapid Fire rules, you send a lot of bullets flying, the more the better chance of at least one hitting, but not nearly all will hit.
It makes shooters "waste" a lot of ammo. The signature of the modern battle is inaccurate automatic fire anyway.

However I'm looking for a way to justify the 3- or 2-round burts so often used, especially in CQB situations these days. Per normal Rapid FIre rules, this sucks, since it's not high enough for a RoF bonus. But these weapons often fire at high cyclic rates. I don't know if all 3 rnd burst capable weapons do this (H&K MP5 for instance), but many new ones do.
Should these have effective Rcl reduced by one for these bursts? Are there any rules for this, something I've missed? Somewhere in High Tech perhaps?
And what about weapons boasting "highly effective muzzle brakes"?

We currently play a moden day Mercenary campaign, and we shoot a lot, mostly autofire.
We have always had some reservations about semi-auto RoF, we tend to think RoF 3 is too much. Perhaps this is ok for autoloader pistols. But a double action revolver requires more pressure. Or a pump action shotgun.

One of the major GMs insists on RoF 2 for semi-auto single shots. ALso, he insists that two such taps at the same target *still* requires 2 seperate skill rolls. Rather than just one, with the Rcl and the margin of succes needed for hitting with the second shot. Because of the "jerk" of the gun with each trigger pull.
Personally I'd keep it to one roll.

However I still have a beef with multiple shots with multiple trigger pulls. A pump action shotgun, how fast should it shoot?
I thin RoF 3 is way too fast. Sometimes I even think 1 is enough.

I'm thinking of lower RoF for a lot of weapons, and a "multiple trigger-pull" or "multiple action" penalty for firing extra.
Autoloader pistols RoF 2, RoF 3 with -2
Automatic longarms on semi-auto fire (or multiple limited burst), RoF 2, RoF 3 with -1
Double Action Revolver, RoF 2, RoF 3 with -4 (only -2 if hammer is manually cocked before first shot)
Pump Action Shotgun RoF 1, RoF 2 with -4

And is the Lever Action faster or slower than a Pump Action? And which "jerks" the gun more?

Anybody do this differently?
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