Author Topic: Del's Primitive Crossbow  (Read 18070 times)

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Offline Del the cat

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    • Derek Hutchison Native Wood Self Bows
Del's Primitive Crossbow
« on: October 29, 2011, 02:15:01 pm »
31" ntn with some built in deflex Laburnum (from one that died in the garden a year or so back) backed with rawhide.
80# @ 12.5"
No metal in the construction. The bow curved upwards so the string doesn't press down hard on the stock, and there are a few nice touches like a sliver of Ivory to stop the bolt being push back too far.
A full build along is on my Bowyers Diary starting here. http://bowyersdiary.blogspot.com/2011/10/graingram-scales.html
I'll take it up the club to the Samhain festival tomorrow.
It certainly shoots clean and fast, no real kick, just a nice click & twhack.


I'll post the speed tomorrow, anyone care to guess >:D
The butt end looks a bit white as it isn't properly finished/varished yet.
Full draw shot ..

Just did some chrono tests. With the heavy bolt in the pic (it has a flat head nail in the butt end for added weight) it was only about 125 fps, but going to a V light bolt (50gn point) it shot upto 170fps. With such a short power stroke I s'pose the heavier bolt slows it down a lot.
I had a couple of dry fires as trigger groove needed a bit of fettling... dind't scare the cr*p out me at all O:).
BTW the string is 90 strands of linen thread. The binding for the prod is hemp twine soaked in a mixture of beeswax & linseed oil.
All fixed now :)
Del
« Last Edit: October 30, 2011, 05:08:30 pm by Del the cat »
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blackhawk

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Re: Del's Primitive Crossbow
« Reply #1 on: October 29, 2011, 02:28:41 pm »
Cool Del....more photos? How bout a full draw :)

Offline Del the cat

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Re: Del's Primitive Crossbow
« Reply #2 on: October 29, 2011, 02:55:09 pm »
I've just added full draw and I'm going to edit in the chrono results.
Del
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Offline ken75

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Re: Del's Primitive Crossbow
« Reply #3 on: October 29, 2011, 03:07:51 pm »
thats pretty cool there "cat daddy", i half expected to see a clothes pin on top  >:D

Offline Matt S.

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Re: Del's Primitive Crossbow
« Reply #4 on: October 29, 2011, 03:10:54 pm »
That's incredibly cool, I'll take a look at your build-along. I'd love to make a crossbow, so I'll be adding this to my bookmarks  :)

Offline crooketarrow

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Re: Del's Primitive Crossbow
« Reply #5 on: October 29, 2011, 03:45:17 pm »
  SWEETTTTTTT
DEAD IS DEAD NO MATTER HOW FAST YOUR ARROW GETS THERE
20 YEARS OF DOING 20 YEARS OF LEARNING 20 YEARS OF TEACHING

Offline Ifrit617

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Re: Del's Primitive Crossbow
« Reply #6 on: October 29, 2011, 05:31:35 pm »
That is awesome! I am curious though how much the bolts weigh?
Given enough time, any man can master the physical. With enough knowledge, any man can become wise. It is the true warrior who can master both... And surpass the results. - Tien Tai

Offline Del the cat

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Re: Del's Primitive Crossbow
« Reply #7 on: October 29, 2011, 06:10:10 pm »
That is awesome! I am curious though how much the bolts weigh?
The heavy bolt (11/32") in the picture is 440gn @ 125fps = 20.7 Joules of energy
A ight bolt (5/16")                                    150gn @ 170fps = 13.0 Joules of energy
The heavy bolt goes pretty slow, but being 4 times heavier ends up having much more energy.
It would be interestion to plot loads of different weights and see which actually gives most energy.
BTW the bolt has just 2 flights fixed at a slight angle to help it spin.
Del
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Offline ErictheViking

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Re: Del's Primitive Crossbow
« Reply #8 on: October 29, 2011, 07:54:54 pm »
Really cool Mr. Cat, that binding for the prod is sweet looking. whole thing is top shelf .
"He that but looketh on a plate of ham and eggs to lust after it hath already committed breakfast with it in his heart"  C.S. Lewis

Offline Ifrit617

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Re: Del's Primitive Crossbow
« Reply #9 on: October 29, 2011, 08:08:42 pm »
That is awesome! I am curious though how much the bolts weigh?
The heavy bolt (11/32") in the picture is 440gn @ 125fps = 20.7 Joules of energy
A ight bolt (5/16")                                    150gn @ 170fps = 13.0 Joules of energy
The heavy bolt goes pretty slow, but being 4 times heavier ends up having much more energy.
It would be interestion to plot loads of different weights and see which actually gives most energy.
BTW the bolt has just 2 flights fixed at a slight angle to help it spin.
Del

Cool, I think Im gonna have to try this sometime.
Given enough time, any man can master the physical. With enough knowledge, any man can become wise. It is the true warrior who can master both... And surpass the results. - Tien Tai

Offline bubby

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Re: Del's Primitive Crossbow
« Reply #10 on: October 30, 2011, 04:21:33 am »
that'a sweet cross bow del, did you wrap the rawhide with cord to get the corregated look, Bub
failure is an option, everyone fails, it's how you handle it that matters.
The few the proud the 27🏹

Offline TBod

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Re: Del's Primitive Crossbow
« Reply #11 on: October 30, 2011, 06:01:50 am »
Very nice!

Any shooting video? I'd like to see how you hold it.


Offline Del the cat

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Re: Del's Primitive Crossbow
« Reply #12 on: October 30, 2011, 06:05:56 am »
that'a sweet cross bow del, did you wrap the rawhide with cord to get the corregated look, Bub
Yup, spot on, that's exactly what I did.
Del
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Offline Del the cat

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Re: Del's Primitive Crossbow
« Reply #13 on: October 30, 2011, 06:11:27 am »
Very nice!

Any shooting video? I'd like to see how you hold it.
None yet, but I hold it like a modern rifle, the butt droops down about half an inch and has a bit of a cast off to the right so with my cheek on the butt my eye is right in line with the bolt.
It's a bit of a mix of styles really, it doesn't look that primitive and there's a hint of the Gothic in that bolt clip. Early crossbows had a dead straight norrow stock, but would imagine it wouldn't take longe before some guy made his a bit more comfortable to shoot. The long straight stocks are a pig to shoot as it's not comfortable however you hold 'em.
The bigger one on my website is a bit of a cheek rattler, there's a vid of that one on my website and it shoots pretty similar to this one.
Del
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Offline TBod

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Re: Del's Primitive Crossbow
« Reply #14 on: October 30, 2011, 02:50:23 pm »
Yes I saw that video "game over" :)

Must be difficult to hold a straight stock crossbow against you shoulder. Is it not sufficient to rest it against your cheek. (maybe grow a beard or something if it hurts to much)