Christmas came a bit late to Gaming Ballistic, but I found myself with a gift certificate to Cabelas. Since my wife and daughter both have bows, I decided I wanted one as well. 

I debated on compound bow vs. recurve, but I’ve always been a sucker for the simplicity of the recurve. It’s not a traditional longbow, which would have been awesome, but nonetheless it’s what I found myself with.

I’ll take it!

I asked for what they had in the 50# range (I wanted a strong-ish bow, and 50# is olympic standard), and stepped up to the firing line to trial the bow. First shot felt nice. I was told to “aim at the fish,” which as a 1″ wide, 3″ long yellow foam thing stuck to the target. 

Second shot . . . hits the fish.

“I’ll take it.” 

I picked out a dozen feathered arrows that are probably a bit strong for the bow. The first sales guy I was trying to talk to was a bit of an asshat, so I wound up with the wrong arrows (55/70 instead of 45/60). 29″ shaft (we measured at full draw) and a dozen 100gr field tips that somehow never made it into my bag. 

Alas, but that’s only $10. 

The results of the shooting were pleasing enough that I just bought the thing. I’ll pick up some more points, and my family will try and find an archery club here in Minneapolis to start practicing more regularly. Shaeffer Archery nearby has an indoor range, so perhaps that’s the ticket.

The Deadly Spring – Thundor Takedown Bow

The bow itself can be worked out using The Deadly Spring. There are a lot of inputs, but cutting to the chase, the riser (non-working section of the bow) is 1/3 the total, while the limbs are 2/3 – this is obvious when it’s taken down, because each section is basically the same length.

The inputs include fiddling with the limb thickness and a bunch of other stuff. Net/net, the model predicts a velocity of the shaft on the order of 200-210fps, Acc 2 (not great – maybe not enough), and a $300 price, which is probably a bit less then 2x higher than I paid for it. That’s OK, though – it’s designed with GURPS prices in mind. 

If I give it the “Cheap” modifier, the price is nearly exactly correct, but that would make it Acc 1, and I’m fairly sure that’s not accurate enough. I mean, it’s not an Acc 4 olympic recurve for actual Olympians, but perhaps it needs the “cheap is good, good is fine, and fine is very fine”  type adjustment that knives get.

Penetration is poor with field tips – as it should be. it’ll clock in at about 1.25 – 1.35 points of penetration including the armor multiplier of (0.5) for the field tips. If we slapped on a forged, barbed, heavy war point (about 500gr for the point, 250gr for the shaft) then damage would increase by a tiny bit, but not enough to eke out more than 1d-1 (1) imp or even 1d-1 (2) imp. More likely than the 2 is that it would increase penetration by about one point, which would make it about 1d imp. That heavy arrow would take the max range down to about 195 yds, and it will do full damage to the full range of the arrow’s fall.

How good was that shot?

I can’t wait to take it out for enough target practice to calculate a bow skill. But first, we look at the bonuses that I get for having all the time in the world and no orcs piling out of the clothing aisle trying to kill me. The light was good, the range was known, etc.  That’s good for probably a +9 bonus (!). The size of the target is probably 1″ x 3″ about 3x the size of an eye, which makes it about -7 for size, and about -4 for range (11 yds is technically -5, but it’s . Accuracy is probably about +4  for the bow, 2 more for a long aim). That’s about +1 or +2 to skill net. If I’ve got a single point in bow skill, Bow-9 would be adjusted to Bow-10 or Bow-11, which would actually give me about a 50-62% chance to pull off this trick. Also, All-Out Attack (Determined) helps. If I’m shooting from Default, it’s probably Bow-6 or Bow-7 (with Dabbler), which again would wind up Bow-9 or Bow-10, for about a 1 in 3 or 1 in 2 chance of putting an arrow on target – that seems not-wrong to me. I need a huge amount of bonuses to pull that off, but I have them, so I’m probably Bow-6 to Bow-9 as an estimate. Not spectacular, of course – but then, that is a testament to the quality of the rules. If I needed to self-identify as Bow-14 to pull this off, that’d be a problem.

Once again, over on the forums there’s a thread. In this case, someone created a repeating crossbow that is re-loaded using a pump-action similar to a shotgun. The design on the thread was a fairly standard design, nothing quite as elaborate as the image to the right.

So, what would I make of such a beast?

Well, compared to a regular crossbow – especially one with modern materials, you’re probably still looking at a draw length on the order of 7-11″ and not too much more. Maybe you could eke out 16″. Modern crossbows have a power stroke of 9.5 to 13″ so you’re not really losing much there. Medieval crossbows were shorter strokes, mostly – the powerful ones had steel limbs that didn’t flex much, and so might be hundreds of pounds – or even thousands – with only 6-9″ of stroke. 

Still, let’s say that we can neglect draw length or power stroke. 

So that leaves the draw weight of the thing. How heavy could that be?

The Basic Set and Low-Tech crossbows leave quite a bit to be desired from a verisimilitude perspective. But let’s assume that the work I did in The Deadly Spring wasn’t totally bogus. That means that you can span a crossbow of up to 8xBL using two hands and bracing the thing on the ground – equivalent to a Two-Handed Lift from p. B353. This seems to be “ready the crossbow in two seconds, ready a bolt, put the bolt on the crossbow,” and shoot on the fifth turn. A bow is ready an arrow, mate the arrow to the bow and draw, shoot. 

So if the lifting part is 8xBL in 2 seconds, and a bow is up to 2.5xBL in one second (slightly generous over the 2xBL from p. B353), how heavy a draw might one manage?

Certainly not 8xBL. No legs or back in use, really. Can we eke out the same 2.5xBL as a bow? Probably not. A bow can use the legs (see my longbow draw movie – it’s not great form, but it’s more than just the arms and back. You get a lot of back and shoulder in it, though.

The pump-action will brace against the shoulder, but it’s pretty much a one-handed pull with one arm, if the second hand remains in “trigger” position and you’re bracing the weapon at the shoulder the entire time. I’m inclined to say between 1xBL (seems light) and 2.5xBL (seems heavy). Let’s give it the benefit of the doubt and say between 2x and 2.5xBL.

Still, the crossbows that do thr+4 imp are the 8xBL ones. The energy you’ll get out of equivalent draw length but less force will be quite a bit less, corresponding to a damage of 50-56% of the full-power bows assuming a draw strength of 8xBL. A weapons-grade crossbow from The Basic Set that is ST 12 will do 1d+3 damage, or about 7.5 points. 55% of that is 4.1 points, or about 1d to 1d+1.

That puts at about thr+2 to thr+3 for ST 12, about where GURPS puts the pistol crossbow.

Parting Shot

So it’s a fast-loading pistol crossbow?

That seems right to me. You’re getting the same damage output of a pistol crossbow, but occupying two hands and cutting the bow-centric reloading time from two seconds to one, and avoiding (for a number of shots equal to that of the hopper) the “ready the arrow” and “mate the arrow to the bow/ready the bow” actions. 

So: stats as a Pistol Crossbow, Shots probably becomes something like 6 (reload 1 or 2/second).

Note that if you’re not using full-length projectiles, efficiency will likely be worse and it might knock the damage down to thr+1 instead of thr+2. Smaller projectiles will reload faster.

Note that dropping a 160-lb compound crossbow to 50 lbs (8xBL to 2.5xBL) using The Deadly Spring will drop the energy from 180J to 35J, and that means:

160J compound crossbow: 7.7 points of cinematic-scale damage, 5.4 points “realistic” scale
35J compound crossbow: 3.3 points cinematic scale damage, 2.3 realistic scale.

That is, at ST 10, a regular crossbow should do 1d+2, which is close to the 5.4 points on my “realistic” scale. The low-draw bow will be closer to 1d-1, which is thr+1, and closer to flat thr (2.0 points, or 1d-2) using half-weight arrows instead of the 0.1-lb projectiles assumed in the model.

So my estimate above should probably be thr and can fire every round, but loads 2 projectiles per ready maneuver (you can probably do more with Quick-Ready or some other Technique), or thr+1 with full-sized projectiles, but defaults to one per second (again, load faster with a Technique).

Oh, sure. Lots of people draw heavier bows. But this one is the heaviest I’ve been able to even attempt – mostly due to lack of opportunity. It’s an 85-lb handmade longbow. Well, not that long.

The form makes a big difference. If you hold the bow out and simply pull, it’s a lot harder than a proper warbow draw, which is a lot of legs and back and motion.

Or, as a friend said: “Is that your bow?”

“No. Not yet.

I also got to talk penetration and Lars Anderson with the proprietor of Grey Goose Bows (he also has a YouTube channel), so a good time all in all. He, of course, made the bow I’m drawing.

If I use the design features of The Deadly Spring, I can model this as 85-lb bow that should be made of walnut (I think that’s what he said) and needs to be 73″ long or longer to give a 30″ draw. It’s modeled as a straight/D-section bow about 0.85″ square. Firing a 31″ poplar arrow with a lightweight armor piercing point (about 680 grains), I should be able to fire an arrow to 305 yards. It will do about 1d penetration to about 200yds, then 1d-1 from there onward. The velocity of that arrow should be about 207fps on release according to the model.

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Stay tuned for more Orcpower posts, as I get into the fighter class. An appropriately optimized (well, more than just whacking something with a sword) Champion, plus Battle Master to help one’s friends is on the way.

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As promised, the video of my drawing the bow.

I was pointed to a rebuttal of the Lars Andersen claims about high-speed archery.

I’ll repost it here:

A Response to Lars Andersen: a New Level of Archery

As someone that wrote a fairly substantial article on the physics of building and bending bows, I’ve followed the entire re-emergence of the original video interesting, and this time the responses to it have been more measured and some of them downright scholarly.

Anyway, the rebuttal is quite interesting, and worth a watch.