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Old 05-10-2016, 10:03 AM   #1
Varyon
 
Join Date: Jun 2013
Default Handling Long-Range Musketry

This is a spin-off from the What kinds of firearms would people start making [After the End]? thread, wherein there was some debate over how accurate smoothbore muzzleloaders should be, with a nod toward their strange exterior ballistics (namely, that they have a bad habit of deviating from their aimpoint more rapidly than standard GURPS Range rules suggest - this is due to a combination of factors, from not being a perfectly-smooth sphere to changes in trajectory due to spin).

Based on the numbers from a Master's thesis linked in that thread, I think I have an idea of how to handle this in GURPS. In that, at some point between 50 yards (-8 to hit) and 80 yards (-10 to hit), the projectiles picked up somewhere between -3 and +2 to skill, with an average of -0.111 (I approximated this using 1d-4). Beyond this, there was something like a further -1 to hit at each -1 from Range, for a total of -2 per point of Range. The shots only went out to about 170 yards, however.

Still, from this, a bit of a pattern emerges. A low resolution solution is to double all Range penalties beyond 70 yards, so that a musket sees range penalties as (...-7, -8, -9, -11, -13, -15, -17...). A bit higher resolution option would be to replace the first -1 with 1d-4, and you could possibly push the range back a step, with (1d/2)-2 beyond 50 yards, rounding normally (so you'd be between -1 and +1 to hit). A much higher resolution option would be to do something like (1d/2)-2, 1d-4, 1d-5, 1d-6, 2d-10, 2d-11, 2d-12, 3d-16, and so forth (although I'd replace each nd with 1dxn, so that you don't get a tighter spread with each added die).

The range at which this starts to come into play is going to vary. The above is perhaps appropriate for an Acc 2 weapon (not certain how good the weapon used in the testing was). Each +1 to Acc from being Fine (Accurate), opting for Careful Loading, and so forth, is +1 SSR to the range beyond which the above effect comes into play. Higher-quality ammunition may also be available - while typically below GURPS resolution, such ammunition is double cost but is +2 SSR to the above range (and this does stack with Accuracy modifiers). Each -1 to Acc from being Cheap, black powder fouling, and so forth, is -1 SSR to the above range. Using field-expedient projectiles drops the range due to Acc penalties and gives a further -2 SSR to the range.

Do keep in mind that, with the sorts of penalties the character is already going to be suffering for Range (by default, the above rules kick in at 100 yards, or 70 if using (1d/2)-2, which correspond to penalties of -10 and -9, respectively; a base Acc 1 pistol firing field-expedient projectiles is about the worst situation possible, and even it doesn't see an effect until it's at -7 or -6 from Range), the above typically isn't going to make much difference, and can probably be safely ignored in most campaigns. If a musketeer sniper harms your Sense of Disbelief, however, the above is a way to handle that. If using Tactical Shooting, note that the above modifiers come into play after the MoA-based skill cap.

Last edited by Varyon; 05-10-2016 at 02:52 PM.
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Old 05-10-2016, 02:18 PM   #2
swordtart
 
Join Date: Jun 2008
Default Re: Handling Long-Range Musketry

I was looking at HT and was surprised to see that the Brown Bess is ACC 2, whilst the Baker rifle is only 1 better at ACC 3. Given the fact that the Baker was the sniping weapon of it's era this seems a bit poor.

I presume all the listed ACC mods are in some supplement that I don't have. Can you cite the books they appear in so I can hunt them down.

I did refresh my memory of ranged combat and it was is somewhat different to how I remember it. The I realised I was still thinking in terms of 3rd edition.

It seems to me you could hand wave all this away by simply lowering the base ACC for smoothbores. The indication is that they were not aimed (very few munition weapons have any sort of sight) but simply pointed. What if we are looking at this the wrong way. Not that they were inaccurate because they were not aimed, but that because they were inaccurate aiming provided no advantage.

There were exceptions and some guns had tube sights etc. but these could be the FINE guns you mention. By carefully controlling the powder, selecting a good ball and loading carefully to avoid distorting it you could achieve fair results.

ACC 2 allows you to shoot at +4 after two seconds aiming. Do those ACC modifying rules allow you to exceed the normal 2x base ACC rule? If not you would be better just aiming a bit (and 2 seconds isn't that long if you can only fire every half minute or so).

If you lower the ACC of the musket to 1, you can at most add another 1. ACC 2 makes hits at 50 and 100 yards hard, but not impossible, but it quickly shifts the 150+ range shots into the miraculous.

I also note in the 3rd edition Wild West that shotguns had a maximum range of 150 yards. That would be another way to handle it. Unfortunately in the same book the Indian musket has a range of almost a mile and a half. How? By using it like a howitzer?. I don't think these wacky numbers are confined to 3rd edition products.

Last edited by swordtart; 05-10-2016 at 02:23 PM.
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Old 05-10-2016, 03:10 PM   #3
Varyon
 
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Default Re: Handling Long-Range Musketry

Quote:
Originally Posted by swordtart View Post
I presume all the listed ACC mods are in some supplement that I don't have. Can you cite the books they appear in so I can hunt them down.
Fine (Accurate)* is found in both High Tech (p79) and Low Tech (p95-96). Careful Loading is similarly found in both books (p86 and p95, respectively). Cheap apparently isn't actually an option for firearms - oops. Black powder fouling is also found in the above books (p86 and p95, respectively). Field expedient projectiles are, yet again, found in both books (p163 and p95, respectively). Finally, the Acc-based cap to final effective skill is from Tactical Shooting (p32). The higher-quality musket balls aren't in any GURPS books and represent balls that are better fits to the musket and are more perfectly spherical. In addition to extending the range before the ball starts deviating from its flight path, such might also serve to give a +2 to the skill cap from Tactical Shooting.

*I erroneously had this as Reliable above; it's been changed, now.

Quote:
Originally Posted by swordtart View Post
It seems to me you could hand wave all this away by simply lowering the base ACC for smoothbores. The indication is that they were not aimed (very few munition weapons have any sort of sight) but simply pointed. What if we are looking at this the wrong way. Not that they were inaccurate because they were not aimed, but that because they were inaccurate aiming provided no advantage.
I don't know how far back it goes, but GURPS Acc actually has a close relationship to the weapon's MoA - you can see this in Tactical Shooting, where Acc serves to allow you to calculate maximum effective skill (which is a function of MoA). It's likely the tested muskets actually do have MoA consistent with an Acc 2 weapon.
I'll also mention something that someone else brought up in the other thread - one good reason not to train your soldiers to aim in formation fighting is that if they opt to Aim, they're likely to do so at the target(s) that stand out the most, which will mean many of your soldiers will be aiming at the same guy, which prevents you from properly spreading out the destruction (better to hit 3 guys with 1 bullet each than 1 guy with 3 bullets...).

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Originally Posted by swordtart View Post
ACC 2 allows you to shoot at +4 after two seconds aiming. Do those ACC modifying rules allow you to exceed the normal 2x base ACC rule? If not you would be better just aiming a bit (and 2 seconds isn't that long if you can only fire every half minute or so).
First, it's +Acc the first second, then +1 for each of the next two seconds, so it's actually 3 seconds of aiming to get that +4 (you can get another +1 by bracing, and a final +1 by making an All Out Attack, of course). Having a Fine (Accurate) weapon, or using Careful Loading (or the more modern equivalent, Match Grade ammunition), actually boosts the weapon's base Acc, so you use the new Acc for things like the skill cap, Precision Aiming, and so forth.

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Originally Posted by swordtart View Post
If you lower the ACC of the musket to 1, you can at most add another 1. ACC 2 makes hits at 50 and 100 yards hard, but not impossible, but it quickly shifts the 150+ range shots into the miraculous.
I'd want to get some more concrete numbers on what sort of MoA muskets see before I did this. Granted, a musket that lacks any sort of proper sights should probably have -1 to Acc.
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Old 05-10-2016, 03:47 PM   #4
Ulzgoroth
 
Join Date: Jul 2008
Default Re: Handling Long-Range Musketry

There was a thread relating to the 2xAcc cap recently...I'm pretty sure the conclusion was that it applied to aiming aids but not to the +2 for extra seconds of aim. (That is, an unmodified Acc 0 weapon's aim bonuses go 0, +1, +2 for 1-3 seconds.)
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Originally Posted by Varyon View Post
Cheap apparently isn't actually an option for firearms - oops.
I can't find a Cheap option either, but GURPS authors occasionally think there is one...
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Originally Posted by Varyon View Post
I'd want to get some more concrete numbers on what sort of MoA muskets see before I did this. Granted, a musket that lacks any sort of proper sights should probably have -1 to Acc.
There's a very interesting, though possibly problematic, box on page 41 of Tactical Shooting relating to this. It includes halving Acc for a gun with misaligned sights and reducing it to 0 if the sights are destroyed.

The problem with this, of course, is that there are lots of weapons with no sights and non-zero Acc values throughout the books...
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Old 05-10-2016, 03:55 PM   #5
Ulzgoroth
 
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Default Re: Handling Long-Range Musketry

Quote:
Originally Posted by swordtart View Post
I also note in the 3rd edition Wild West that shotguns had a maximum range of 150 yards. That would be another way to handle it. Unfortunately in the same book the Indian musket has a range of almost a mile and a half. How? By using it like a howitzer?. I don't think these wacky numbers are confined to 3rd edition products.
I can't say much about 3rd edition numbers, but the shotgun range is probably wrong by modern standards. (If that's for firing shot, it may have meant something different at the time? I know autofire and shotgun rules were different in 3e.) The musket might be as well, but having the maximum range require high elevation isn't unusual. (In High Tech at least one stat line is specifically noted as having much shorter maximum range than the theoretical limit because it's a tank gun, and in the tank mounting it had restrictive elevation. That's the 7.5cm KwK40 on p141.)
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Old 05-10-2016, 04:09 PM   #6
Polydamas
 
Join Date: Jan 2006
Location: Central Europe
Default Re: Handling Long-Range Musketry

One question to ask would be whether the rules for musket accuracy are any worse a fit than for the performance of stones, arrows, or .50 BMG rounds. GURPS rules try to be in the right ballpark while being simple enough for ordinary people to use after a long day at work and without spending more time and book money than GURPS players are willing to pay for.

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Originally Posted by Varyon View Post
Fine (Accurate)* is found in both High Tech (p79) and Low Tech (p95-96). Careful Loading is similarly found in both books (p86 and p95, respectively). Cheap apparently isn't actually an option for firearms - oops.
High Tech p. 10 does say that the cheap modifier printed on that page is not available for firearms, but the cheap/good/fine options were created to describe edged weapons, and examples of cheap firearms (and effects of cheap quality, such as dangers using Extra-Powerful Ammunition HT p. 165) are scattered throughout High Tech. My copy of the basic set is in the old country, but a simple way to read this would be that cheap firearms have idiosyncratic costs and disadvantages, such as reduced Malf, rather than stats which can be generated by algorithm from a base entry.
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Last edited by Polydamas; 05-10-2016 at 04:17 PM.
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Old 05-10-2016, 04:22 PM   #7
johndallman
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Default Re: Handling Long-Range Musketry

Quote:
Originally Posted by Varyon View Post
Cheap apparently isn't actually an option for firearms - oops.
It appeared in After the End 1, p32, after having been on PK;s MyGURPS site for several years.
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Old 05-10-2016, 04:41 PM   #8
Anthony
 
Join Date: Feb 2005
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Default Re: Handling Long-Range Musketry

The GURPS range rules in general are more of a gameable hybrid than anything resembling modeling of real world performance; firing under controlled conditions is much more reliable and has much faster performance dropoff than the rules in GURPS. This is, most likely, because your skill in GURPS includes effects other than "did you aim in the right place" -- when someone misses at 2 yards, that's not because of the accuracy of their weapon.
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Old 05-11-2016, 01:23 AM   #9
Tomsdad
 
Join Date: Jan 2010
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Default Re: Handling Long-Range Musketry

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Originally Posted by Anthony View Post
The GURPS range rules in general are more of a gameable hybrid than anything resembling modeling of real world performance; firing under controlled conditions is much more reliable and has much faster performance dropoff than the rules in GURPS. This is, most likely, because your skill in GURPS includes effects other than "did you aim in the right place" -- when someone misses at 2 yards, that's not because of the accuracy of their weapon.
If reality is that accuracy in general is maintained for longer but then drops faster past a certain point, that to me that sounds like the underlying issue is how range table spaces the range penalties by distance.

I also quite liked systems that recognise that different weapons/set ups are best suited for different ranges (i.e not just a bonus to all shots which you apply to all ranges)

Last edited by Tomsdad; 05-11-2016 at 03:54 AM.
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Old 05-11-2016, 01:39 AM   #10
Polydamas
 
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Default Re: Handling Long-Range Musketry

When as a teenager I plugged some of those 19th century musket tests against fixed targets into the GURPS model, I had no problem reproducing them with reasonable skill levels. YMMV.

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Originally Posted by Tomsdad View Post
I also quite liked systems that recognise that different weapons/set ups are best suited for different ranges (i.e not just a bonus to all shots which you apply to all ranges)
I would be surprised if those other systems are any more accurate than GURPS if you look closely at the numbers and compare experimental data. And can you imagine how much work it would be to get performance at different ranges under combat conditions for every weapon in High Tech?

I have never had a game session be less fun because a weapon performed slightly differently than it probably would in the real world, if the real world had magic, demons, and Gunslinger. Sometimes we shrugged and said "that is not not we think it works, but changing the rules would be too much work and might not be any better, so lets do what they say and get on with the adventure."
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Last edited by Polydamas; 05-11-2016 at 02:13 AM. Reason: Fixed typo
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