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Impressive design, to be sure. Shows that some people were really smart way back when :)

Certainly an implementation of high energy storage, and with heavy arrows, a fantastic 95% dynamic efficiency...

Keep in mind, though, that they're doing a 32" draw. Not really an apples to apples with a 28" draw comparison...
 
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Impressive design, to be sure. Shows that some people were really smart way back when :)

Certainly an implementation of high energy storage, and with heavy arrows, a fantastic 95% dynamic efficiency...

Keep in mind, though, that they're doing a 32" draw. Not really an apples to apples with a 28" draw comparison...
More like Macintosh v Red Delicious? ;)

Found this for longbows drawn 32 inches:

"The Great Warbow" - Matthew Strickland and Robert Hardy

210fps at 5.5gpp, 340 yds
190fps at 7.6gpp, 280 yds
175fps at 9gpp, 250 yds

150# bow at 32 inches

Which is close enough to the 170fps/1230g/128lb/9.6gpp for the longbow in the Manchu link.

Then again, this is one test of a Manchu bow; don't know if can/has been repeated/verified w other bows by other people.
 
More like Macintosh v Red Delicious? ;)

Found this for longbows drawn 32 inches:

"The Great Warbow" - Matthew Strickland and Robert Hardy

210fps at 5.5gpp, 340 yds
190fps at 7.6gpp, 280 yds
175fps at 9gpp, 250 yds

150# bow at 32 inches

Which is close enough to the 170fps/1230g/128lb/9.6gpp for the longbow in the Manchu link.

Then again, this is one test of a Manchu bow; don't know if can/has been repeated/verified w other bows by other people.
Good comparisons :)

I was thinking of other tests. My bad...
 
240 lbs!? It's amazing what archers did when it was a matter of life and death, not just fun and games? ;)
I wonder if that guy's last name was "ballista" :)

It is really interesting to think there was probably no counter-measure for these warbows... the light bows of asian and muslim archers I always thought were just as effective (speed kills) but then I read this:

Saladin’s secretary Beha al-Din, had a very different take on the effectiveness of muslim arrows against the crusaders. He writes that "Their infantry, drawn up in front of the horsemen stood as firm as a wall, and every footsoldier wore a thick gambeson [padded jacket] and mail hauberk so thick and strong that our arrows had no effect. I saw soldiers with from one to ten arrows sticking in them still trudging on in the ranks."
 
If we thought it were possible we would have tried it. you would need a very long limb to keep the angles good, and the reason for that is because of the forward preload needed to keep the bulge on the DFC going.

When you preload a longbow limb you do tend to shorten its DFC but you do increase the preload. kinda good but you get stack at longer draws. So if you went for a longer limb, you can elongate that DFC.
but that comes with mass.
so there is a cross over in mass and energy.

what we find interesting, is that the weight of a single inch of limb for glass is heavier than it is for a carbon limb. So limb mass becomes a smaller player.

so its possible to design a bow with a longer limb extending the preload bulge out. but with less negative effects.

(considering you still need to keep vertical stability and stop it turning into a complete noodle)
Needle tips could help with the mass, to a point, but I'm having issues with noodling. Any thoughts on stiffening tip wedges helping with noodling?

Fast recurves make me look stupid:lol:
 
Very interesting............... and made more interesting by the quality commentary.

I see that ancient bow and wonder how the discussion went way back when, "Emperor, The archers are ready for battle....would you like the good news or the bad news first"
"Well Emperor these bows are incredibly efficient................but almost 1/2 of our archers are seriously injured while attempting to string them"
 
Vertical noodling I suppose it would be, not left/right alignment. I have issues with the string curling around one limb or the other on really reflexed limbs, even when the tiller is even.
 
Vertical noodling I suppose it would be, not left/right alignment. I have issues with the string curling around one limb or the other on really reflexed limbs, even when the tiller is even.
could be LOTS of things.
but an increase in BH gets rid of it.

A change in former profile also does the same. More aggressive limb angles at the fadeout can help.

or one fade out is stronger than the other. ie the source of the tiller is not even on both limbs.

but these can be the main sources.

weakening the outer limb by traping is can simulate the higher BH, BUT it does depend on the source of the problem

all this is in our experience... others might have different answers...

Is this for a Takedown longbow limb?
 
Yup, three piece lonbow. I had luck with lightenning the tips some, as well as shortenning them. Brace height increase worked, but losing too much power stroke seemed like a poor trade off.

Hmmm...
 
you will see that most ILF limbs struggle with this floppy shape until you get a high Brace. which as kegan said. Has a poor DFC.

I'll Post a pic of what we did to our LB limbs to solve some of this problem
 
Ive borrowed a couple of photos from someone else here... but as you can see, we have made thick ILF limb butt at the rockers. to kick the limb forward, making the best of a bad angle. Longbows don't like recurve geom...






With ILF there are two places of contact, under side of the bolt. and the rocker. You either need to wind the bolts in, or push the rocker out... we did the latter.


This reduces the needed BH. without giving you a horrible limb shape needed to get the energy up.

At least that's our thinking.

We don't have any limbs with any glass in them. so the limbs are light, but adding mass at the limb butt isn't a problem...
 
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