Ancient bows from Mongolia from an exhibition in Bonn Pt. 3

Adam Karpowicz · Post by **Adam Karpowicz** » Tue Jan 31, 2012 4:37 pm

Tips can be pretty small even in very heavy bows - have a look at the Turkish ones. I guess we have to make one of these bows to be sure...

At 1.4cm the bow would be 80+lb. This is all for 28in draw. I suspect these bows, being rather long, were drawn further than that.

Adam

Dusan · Post by **Dusan** » Tue Jan 31, 2012 10:02 pm

Nice picks JJ.Thank you.

Patrick Menzies · Post by **Patrick Menzies** » Wed Feb 01, 2012 2:48 am

But the turk bows seem to have an insert and wrapping. I don't see anything but wood in this siyah.

JJ · Post by JJ » Wed Feb 01, 2012 7:33 pm

Patrick, this bow indeed has nock inserts, while the other two don?t have them. I saw them on display, but they are not very visible on the photogaphs because of backlighting. I will try to post a pic anyway. They consist of very narrow strips inserted vertically at the string groove.

JJ

JJ · Post by JJ » Wed Feb 01, 2012 7:45 pm

Sorry for the bad quality...

The material of the insert appeared to me like a sort of dark horn.

BTW, in the catalogue you find an x-ray of the handle and it shows lateral reinforcement, probably of horn, there.

JJ

TZH · Post by **TZH** » Fri Feb 03, 2012 8:50 am

Fusizoli linked this wonderful bow on his forum. I'll go to Germany in april, and hopefuly able to visit the exhibition.

I got a pic (Bibarcfalva, Transilvania) from a friend, it shows a hungarian archer, painted in the early 1400's.

Fenris · Post by **Fenris** » Fri Feb 03, 2012 9:34 am

Adam Karpowicz wrote:Tips can be pretty small even in very heavy bows - have a look at the Turkish ones. I guess we have to make one of these bows to be sure...

At 1.4cm the bow would be 80+lb. This is all for 28in draw. I suspect these bows, being rather long, were drawn further than that.

Adam

Hi everybody,

I' ve been visiting this forum since quite a long time now and found my first chance to just jump in an help out with a bit of information aacording to draw weight. The much discussed observer of the bows claims to have build an exact copy (down to fractions of a millimeter) of the second bow JJ showed in his posts. He states that before shooting it the draw weight was about 80 lbs on 28 ".
He also build copies of the other bows and claims that the draw weight ranges between 60 and 80 lbs at 28". The short draw length is supported by the length of the arrows found along with the bows. He claims the same to be true for the spine of the arrows that is siutable for bows at about 60-80 lbs.

Regards Kevin

Adam Karpowicz · Post by **Adam Karpowicz** » Fri Feb 03, 2012 11:24 am

That may answer the question of draw weights. Any chance we can get the dimensions of the bows from this bowyer?

Adam

Fenris · Post by **Fenris** » Fri Feb 03, 2012 1:28 pm

Due to the fact that he is the author of several publications in this topic he has to be quite secretly about giving measurements or photos in a forum. But in reference to his statement at "fletchers-corner" the complete build along and measurements are given in the catalog of the exhibition http://www.primusverlag.de/titel.php?ar ... 2273684785, that is in german. Maybe somebody else (JJ?) already has got the catalog and can give the measurements.
Interestingly I had a little dispute with the author some time ago about the measurements and the possibility of calculating the draw weight from it. He doubted the the accuracy in this method. As an example he gave the measurements of a mongol bow he just recently build: length 140 cm, thickness in the middle of bending area 14 mm (6 + 5 + 3 mm) and 80 lbs of draw weight. It would be a bad coincidence if he did not mean this bow out of the exhibition. The numbers in brackets (6+5+3 mm) refer to the thickness of sinew, wood and horn. He did not specify which is what. Wood of 5 mm thickness is obvious. On the other hand he did not specify wether the 6 mm is horn or sinew. From the context of the discussion he meant 6 mm sinew and 3 mm horn in his reconstruction. Also this seems quite possible to me, cause I would assume that in this design the bowyers added more sinew to prevent the bow from breaking apart (wrapping around) than in a turkish design, where the sinew would be around 3 mm and the horn 6 mm.
Besides all speculations it is for sure better to get the book along with the measurements to build a copy

Besides that I have to give credit again to your method in calculating the draw weight: I took a Avar referece design where I knew the measurements and the draw weight and used the formula given in your book with the measurements he gave. I ended up at 71 lbs at 28" and 80 lbs at 30 ". He indeed was quite impressed implying that he should get a copy of your book

.
P.S.: The bow after shooting a couple of dozen arrows gave a draw weigt of around 60 lbs at 28". At 9,2 gr/lbs the bow gave an arrow velocity of 162 ft/s with a 28" draw.

Adam Karpowicz · Post by **Adam Karpowicz** » Fri Feb 03, 2012 2:29 pm

Thanks Kevin. The formula is very much simplified, but still allows to compare bows of similar design and of the same draw length. As you say, the differences in the relative amounts of materials can skew the results, plus the reflex during manufacture can be rather arbitrary as chosen by the bowyer. I would not claim the accuracy to be any better than +/-10lb, which is perfectly sufficient for these purposes.

I still believe the bow had to be drawn further than 28" for its length. Perhaps not all arrows were found with the bow.

Adam

Fenris · Post by **Fenris** » Fri Feb 03, 2012 3:10 pm

I totaly agree, especially if one thinks of the better energy storage per weight ratio. Despite that the picture TZH posted shows a much shorter draw length. But anyway who claims the great accuracy of historical paintings

, while there are many paintings showing a draw to the ear or neck ... Probably it differs from archer to archer.

Kevin

Patrick Menzies · Post by **Patrick Menzies** » Fri Feb 03, 2012 5:09 pm

Rather depressing that a replica of a near mythically performing bow only shoots at OK selfbow speed.
Thinking that the longer arrows were somehow missing seems like a grasping at straws scenario.
Eventually things just are what they are.
Those arows shown don't even look that light despite their barreling. Especially with the largest of those heads.

Adam Karpowicz · Post by **Adam Karpowicz** » Sun Feb 05, 2012 2:31 am

Yes, that is depressing. However:

1. The specs of the replica are listed on p. 189 as 80lb@28in before shooting and 60lb@28 after shooting. The drop of 20lb sounds suspicious to me and would worry there was a some kind of internal damage taking place.

2. Arrows 30in long are listed on p.244.

3. One bow does not make statistics.

If someone could gain accsss to the collection and measure all bows properly, we could make more replicas.

Adam

Redhorse · Post by **Redhorse** » Sun Feb 05, 2012 7:03 am

Something must be wrong. A two wood bow 150cm n/n 16 (1-2mm sinew) midlimbs is abuot 65 lb and at 26" shoot faster then those bows. A shorter made of wood, horn and sinew should be much stronger and shoot faster at longer draw. It should at last be stronger, speed can be low because of the mass at nocks.
And what use? hunting or warfare? Less then 60 lb for hunting gives problem in open terrain. Arrow speed less then 180fps in warfare gives problem.
Why would they have build bows that does not give any advantage?
If we look at this bow, some scrap I had, with 30 inch it made 200. So a hornbow should be stronger and faster.

Kviljo · Post by **Kviljo** » Sun Feb 05, 2012 10:22 am

Adam Karpowicz wrote: If someone could gain accsss to the collection and measure all bows properly, we could make more replicas.

Adam

Does that mean that the measurements and documentation of the bows in the exhibition catalogue are not complete or good enough for making a replica?

I just ordered the catalogue, hoping there would be some good material there.

A big thanks to JJ for sharing these brilliant pictures, btw! Wow!