Low-Tech Missile Weapon Range and Accuracy

[Icelander]

Originally Posted by jacobmuller

Okay.
You still need to find ST+1 recruits for bow use. Muskets and Crossbows don't require exceptionally strong recruits.

Not really. The Composite Bow is ST 10 and is better in all ways than the Longbow.

And ST 11+ is pretty standard for professional soldiers throughout history. Not because they need it for fighting, but because soldiers have always had to carry a lot of heavy gear. That won't change no matter what weapons we stipulate.

Originally Posted by jacobmuller

I'd take the RAW Bow stats as correct. About the only change I'd make is finding a way to handle the difference between arrow heads; target, broad, bowel-raker, blunt, etc.

So you think that Composite Bows are as accurate as modern target pistols? And that Crossbows, even in antiquity, were as accurate as the M4?

Originally Posted by jacobmuller

Muskets are powerful enough and they weren't renowned for accuracy. We do, however, have tales of accurate archery/ crossbow shooting. Time was, I could put an arrow in the cup at 50 yards with a borrowed practice bow and used target arrow while using a pin and cellotape for sights. Muskets were deemed remarkably accurate if they could hit a man-sized target at 100 yards.

Musket stats are reality-checked. Bow and crossbow stats aren't. They're legacy code, retained for gameplay reasons and because of the perception that gamers want unrealistically effective missile weapons.

Originally Posted by jacobmuller

Perhaps you're over-rating powder and under-rating muscles?

Find a hoplologist who's done the research and agrees with you.

[DouglasCole]

Originally Posted by Icelander

Not really. The Composite Bow is ST 10 and is better in all ways than the Longbow.

From what I have gathered from mild net usage, the Composite bow is merely smaller and easier to use from hoseback than yew longbows. It was not heavier draw (the amazing mongol comosite bow with draw strength as high as 160lbs, which isn't much different than the 110-180lbs estimate than warbows from Europe), but was more size efficient.

[DouglasCole]

Originally Posted by Icelander

Douglas, regarding the velocity number of 60 m/s, I've found sources (including The Knight and the Blast Furnace) that indicate that 50+ m/s is easily achievable with yew longbows of #75-#80 draw weight. I admit that this is using a 50g war arrow, but a 90g broadhead only slow it down by about 20%. Initial energy would be around 70J-90J.

Shouldn't a #150 yew longbow get more speed?

The same experimenters (McEwen et al) got a speed of 62 m/s with a #90 draw weight crossbow firing a modern target bolt. Energy with a 100g bolt would be 192J.

Can you spin these into GURPS damages?

Modern bows are vastly more efficient than their medieval counterparts, and modern arrow construction allows for better transmission of the energy even beyond the bow's inherent superiority, so I'd be careful there.

Still, I will run some numbers for arrows from 50-100g and impact velocities from 45 to 90m/s to get a range for things. I will assume 8 to 12mm cross sections, just for fun.

[Icelander]

Originally Posted by DouglasCole

From what I have gathered from mild net usage, the Composite bow is merely smaller and easier to use from hoseback than yew longbows. It was not heavier draw (the amazing mongol comosite bow with draw strength as high as 160lbs, which isn't much different than the 110-180lbs estimate than warbows from Europe), but was more size efficient.

In GURPS, it's better in all ways.

Whether that fits reality or not is what I'm trying to figure out with this thread.

I do, however, recall composite bows achieving a higher maximum range than yew longbows of the same draw weight. I've at least read that in a few places.

[Icelander]

Originally Posted by DouglasCole

Modern bows are vastly more efficient than their medieval counterparts, and modern arrow construction allows for better transmission of the energy even beyond the bow's inherent superiority, so I'd be careful there.

This was using period reproductions, not modern equipment. The only modern thing there was the target bolt and the energy given for the crossbow assumes a historical war bolt.

Originally Posted by DouglasCole

Still, I will run some numbers for arrows from 50-100g and impact velocities from 45 to 90m/s to get a range for things. I will assume 8 to 12mm cross sections, just for fun.

Thanks.

[DanHoward]

Originally Posted by DouglasCole

From what I have gathered from mild net usage, the Composite bow is merely smaller and easier to use from hoseback than yew longbows. It was not heavier draw (the amazing mongol comosite bow with draw strength as high as 160lbs, which isn't much different than the 110-180lbs estimate than warbows from Europe), but was more size efficient.

Composite bows are far more efficient that self bows. More of tthe energy is transferred to the arrow. It is likely that they are more accurate too since the hand and arm suffers less vibration. A composite bow archer would be able to pull a heavier bow than a longbow archer of a similar ST. I would allow a +1 ST for a composite construction compared to a self bow.

[DouglasCole]

Arrow Weight	Impact Velocity	Arrow Diameter	Damage (pts)	KE
50	50	8	3.0	62.5
50	50	12	2.7	62.5
75	50	8	3.7	93.8
75	50	12	3.3	93.8
100	50	8	4.3	125.0
100	50	12	3.8	125.0
50	75	8	4.6	140.6
50	75	12	4.1	140.6
75	75	8	5.7	210.9
75	75	12	5	210.9
50	100	8	6.2	250.0
50	100	12	5.5	250.0
100	75	8	6.6	281.3
100	75	12	5.8	281.3
75	100	8	7.7	375.0
75	100	12	6.8	375.0
100	100	8	8.9	500.0
100	100	12	7.9	500.0

Max damage for a 100g arrow at 100m/s is about 9pts, or 2d+2. A 9mm pistol bullet has 581J of energy. A .45ACP is 420J (2d, 11.43mm), and a 5.7x28mm is 514J (2d+3, 5.7mm). I think the 75m/s numbers, which go up to about 6.0 to 6.5pts of damage (about 2d-1) is about as good as you're going to get out of a bow.

[Icelander]

Originally Posted by DouglasCole

Arrow Weight	Impact Velocity	Arrow Diameter	Damage (pts)	KE
50	50	8	3.0	62.5
50	50	12	2.7	62.5
75	50	8	3.7	93.8
75	50	12	3.3	93.8
100	50	8	4.3	125.0
100	50	12	3.8	125.0
50	75	8	4.6	140.6
50	75	12	4.1	140.6
75	75	8	5.7	210.9
75	75	12	5	210.9
50	100	8	6.2	250.0
50	100	12	5.5	250.0
100	75	8	6.6	281.3
100	75	12	5.8	281.3
75	100	8	7.7	375.0
75	100	12	6.8	375.0
100	100	8	8.9	500.0
100	100	12	7.9	500.0

Max damage for a 100g arrow at 100m/s is about 9pts, or 2d+2. A 9mm pistol bullet has 581J of energy. A .45ACP is 420J (2d, 11.43mm), and a 5.7x28mm is 514J (2d+3, 5.7mm). I think the 75m/s numbers, which go up to about 6.0 to 6.5pts of damage (about 2d-1) is about as good as you're going to get out of a bow.

I'm having a hard time deciphering that table, sorry. It's missing damage and KE.

I'm fine with 2d-1 as a realistic damage from an English warbow. But what's the wound channel modifier? The same as your earlier calculation or more? Less?

[Icelander]

Originally Posted by DanHoward

Composite bows are far more efficient that self bows. More of tthe energy is transferred to the arrow. It is likely that they are more accurate too since the hand and arm suffers less vibration. A composite bow archer would be able to pull a heavier bow than a longbow archer of a similar ST. I would allow a +1 ST for a composite construction compared to a self bow.

How efficient is a crossbow compared to a bow of the same draw weight? Roughly?

If necessary, answer seperately for crossbow self-bows, composite crossbows and steel crossbows.

[Kromm]

Originally Posted by Icelander

I'm having a hard time deciphering that table, sorry. It's missing damage and KE.

Nothing is missing. The five columns are, from left to right:

1. Arrow Weight
2. Impact Velocity
3. Arrow Diameter
4. Damage (pts)
5. KE

Units would be good, though.