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As some of you may know, I’ve been stirring around this idea of high-FOC wood arrows. I punched numbers repeatedly through Stu’s calculator, changing point weights, feathers, shaft length etc. using estimated weights for shafts and adjusting spine weights also. Here’s where I’ve come to now:
After much tweaking of the calculator, perusing web sites for information and conversing through threads or PM’s with various knowledgeable folks, I called up Neil Hildebrand, discussed shafts with him, then had him send me some Sitka Spruce shafts in 80-85 spine. I settled on a 225 grain Tuffhead broadhead, so I purchased 3 from Vintage Archery, along with some 225gr brass points. I had previously received some Grizzly 125’s for testing and I purchased some 100 grain woody weights so I could do some testing with broadheads, without using all 3 Tuffheads for practice (saving them for the local wily whitetails). Over the last 2-3 weeks, I have straightened, spined (homemade spine tester ala Jim Hill) and weighed all the shafts, did I mention I straightened them ( a few times)?. The 80-85 spine shafts test out from about 82 to close to 90 on my spine tester and weight from 420 to 438 grains. I then proceeded to cut a few down to desired length. I will admit that I heard that bare shafting wood arrows is a no-no so I kind of went reverse and cut more than I should have off a few before backing up and realizing maybe I should cut less off, then adjust if the flight is not quite right. Guess I’m just a learn by doing type o’ fellah. TIP: I contacted a local sign making shop for some white vinyl, adhesive backed stock for cutting wraps out of.and purchased a 2ft. by 18″ sheet for $5 (or I could have ordered wraps for close to a buck a piece!) The wraps are mostly for later re fletching, and I am cutting them at minimum lengths to match fletching lengths and to lower their weight (4-6 grains each in total wrap weight). Then I fletched a few with 4″ feathers, a few with 3″ feathers, one with 4 4″ feathers and put turbulators on a few. Then I shot them with 225 grains up front, some brass fields, some woody weights (100) and blunts (125 gr). I was seeing some kicky flight, so paper tuned a bit and found that nock point was a bit off and adjusted. Also decided to take my Big JIm’s Strap-on quiver off the bow and this also improved flight characteristics. Here’s a breakdown:
BOP 29.5625″, 4.25″ wrap with 0.125″turb. 3 3″ feathers, 656 gr.
BOP 29.875″, 4.3125″ wrap with 0.125″ turb. 3 3″ feathers, 666 gr, (Tuffhead 225 gr)
3 @ BOP 29.8125″, 5″ wrap no turb., 3 4″ feathers, 1@660 gr.(brass), 2@ 666 gr.(w.weight 100, 125gr blunt)
BOP 29.125″, 5″ wrap no turb., 3 4″ feathers, 652 gr.
2 @ BOP 29.25″, 5″ wrap w/turb, 3 4″ feathers, 1@664 gr. 1@654gr. (w.weight, 125gr Grizzly, both)
So here we see the inconsistencies in grain weights of wood shafts and various components, resulting in different overall arrow weights, but I also take into account the differing shaft lengths. AGain, the wraps don’t add much, like a grain, grain and a half per inch of wrap. I also am using two different nocks, Snap-on 5/16″ and Bohning Classic Index nocks. Interesting note: the Index nocks weigh 10 gr. and the seemingly smaller Snap-Ons weigh 12 gr.
Another interesting thing: When I use STu’s calculators and punch in my component weights, the various combinations calculate to close to if not a little shy of 15% FOC. BUT, when I actually measure Balance point, Length of shaft (nock valley to BOP), and use (B/L -0.5)*100 to calculate FOC, I am getting upper 18’s. More in line with the Ashby suggested FOC of 19% and I am pleased that the shafts are weighing above the 650 grain suggested weight.
Just thought I’d put this out there to show again that it is possible to get 650 gr. 19% FOC arrows using wood shafts, IF you can find the high spined shafts in low overall grain weights.
I am shooting a 62″, 53# @28 Toelke Whip longbow (MTB is her name) and drawing 28.25″.
To restate: I like the design and non-bow marring design of the strap-on quiver but did notice an improvement in arrow flight WITHOUT the quiver on the bow. The bow is no louder with the quiver on or off the bow. I can’t say whether or not there is a difference in shooting-feel, quiver on or off but there was a noticeable difference in arrow flight, perhaps due to balance, slight grip pressure changes due to the added weight or simply bow reaction, quiver vs. non-quiver. Chalk it up to another interesting mystery re: traditional bowhunting gear, instinctive shooting, me vs. another person’s style of shooting, yes, a MYSTERY to be perhaps never solved. C’est la Vie, no? Oui!
Now, the real field test will begin in a little over two weeks when MN Bow opener arrives and I can stop foaming at the mouth and get to enjoying all that my woods experiences will bring. Gawd, do I love Bowhunting! Best of luck to all and may the bits and pieces of your bowhunting experiences add up to a beautiful memory-painting in your mind!
TomBow
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I was playing around the other day with wood arrows and steel insert. I chucked the arrow in my lathe and bored a 1/8″ dia hole about 3″ deep. Then I made up a field point with a 1/8″ rod on the back, where the 3/4″ section that screws into an insert, would normally be. My version of Woody Weights I suppose.
What I envision as ideal is a point like that except instead of a point, it would be drilled an tapped as an insert. It would also be super to have an “arrow shaft diameter” sleve as part of this, and slightly trim the shaft to allow the sleeve to cover it. That would give a greater FOC and make a much stronger wood arrow as well. If I can ever figure out how to add the sleeve to this as a one piece unit, I will build one. The tip of the shaft is NOT tapered, by the way.
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this is not a new concept. a company was doing this in the 80’s, and the sleeve was made of brass. my dad still has a couple dozen of these arrows. if i remember right, they were made by a company called muskege archery.
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I guess good ideas refuse to go away! I wasn’t aware of those arrows, but I must say, I am not surprised. The forefathers of modern archery were full of ideas, and made remarkable strides even though the technology wasn’t there to help some idea reach their full potential.
A CNC machine could spit these things out in about 45 seconds each.
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