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I’m returning to traditional bowhunting after a 20 year absence. (I was fishing.) I now shoot a 66″ longbow, 60lbs.@28″. I draw about 28 1/2″. I’m shooting 2117 alum’s. cut 29 3/4″ long with 125 grain points. I’ve noticed some rub marks on my arrow shafts just in front of the fletching where they rub the plate. After a dozen or so shots, I start to feel a little feather burn on the index finger knuckle of my bow hand. I don’t think these shafts are clearing the shelf properly but they appear to fly well. Are these arrows overspined, underspined, too long???? Is this possibly a problem with my knocking point? I haven’t encountered any traditional shooters in this neck of the woods so I’m counting on you guys for help.
Thanks in advance.
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If your bow was a cut past center recurve I’d think your arrows a pretty good match, but they may be too stiff for your longbow. How deep is your shelf cut? It makes a huge difference in spine requirements. Is your bow a high performance hybrid or something more like a Hill? What string material are you using?
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Best I can measure from centreline of limbs to arrow plate is about 7/16″ – certainly not past centre. The bow is a Robertson “Mystical” Stykbow. I’m not sure if that’s considered high performance. I’ve ordered dacron strings from Robertson but I but I have no idea what grade of dacron they will be. I’m trying to stay away from “fastflight” strings because I have no familiarity with that material.
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Dennis,
I draw my Grizzly recurve to 60 lb @ 29 1/2″, and with a 145/150 gr. tip, I get a nice-flying arrow. My arrows are also 2117’s, but are cut at 31 1/2″. You may want to try a longer shaft or a heavier tip. Try one or the other, but not both as it will weaken your spine entirely too much. Good luck.
Michael.
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Yep, bet they are a little stiff. You should call Dick and ask him about a FF string on your Bow. Would help overcome your spine problem with out buying new arrows. Dacron is great, quiet Bow, but FF will give you a little faster arrow and weaken your existing shafts. Drawbacks, well you’ll have to re-tune a little.
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OK you longbow shooters. I’ve been all through the tuning routine using the Adcock system followed up by shooting through paper at 6 feet just to confirm my findings – nice round hole with a bare shaft. I ended up with 2219s at 628 grains and 15% FOC. (2020s flew nicely as well but I have a bunch of 2219s and deltas to go with them.) A couple of evenings out at our club’s indoor range and my fletchings are showing wear even though I’ve rotated the nocks to give me the best clearance. As I am new to longbow shooting, is this a common occurance? Am I going to be refletching my arrows every few months? I’m used to tuning the bow to the arrows, not the arrows to the bow.
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Dennis- What length and height of fletching- 3 or 4- and right or left hand? Three fletch 5″ right wing will give me the same feather ‘burn’ as you but the same in left wing will not. Have been trying some 4″ with a 90 degree 4 fletch right wing helical and so far no rubbing in my preliminary EFOC arrows. As for shaft rub and the ragged feather syndrome, check to make sure your shelf rest and sideplate do not have any ‘steps’ or edges to abrade- sometimes it helps to glue a matchstick or bamboo skewer piece under the rest right where the deepest of the grip is to provide a single contact for the shaft. Since you’re bareshaft tuned, perhaps some lower feathers will work- template and a sharp pair of scissors- and keep us informed of your results. Since our bows are basically the same once setup, all we’re left to tinker with are our chosen missiles- check out the Ashby Lethality studies and posts.
Good shooting and have fun! Bert(Go Canada!) -
Dennis, if you arrows are hitting the side plate, they are too stiff. Paper tuning will likely confirm this. I’m a wood arrow guy. My Robertson shoots 27″ arrows with 160 points that match spine with draw weight. For yours, I would recommend 65-69 lb spine. Go up a notch if you want to shoot a heavier point.
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Thanks for all the help guys. I’ve ordered another half-dozen 2020s that I’m going to tune to. I’ve also orderd a left wing clamp and a bunch of fletching for my Bitz and some 180 grain field points. I’ll try the 180s and left wing helical (I was shooting right wing)on my 2219s and if that doesn’t work then I’ll go with the 2020s, left wing. I’ve got lots to tinker with – half the fun. I’ll keep you posted.
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Dennis, try the heavy field points on your 2117’s and I think you will see quite an improvement. I think you will be able to tune the 2020’s, too. 2219’s are about a 95 lb spine and will probably be too stiff for your Robertson. They might be a good match for the Grable, tho. Good luck and enjoy the journey!
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Fletcher — while I appreciate all informed opinions on technical questions, it’s really great to have professionals in the mix as well. Thanks for joining us! snuffs:D
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Well I think I’m finally there. I’ve been playing with arrow spine, length, head weight and left or right wing fletching for about 6 months now. And I think I’m now happy with my arrow performance. I started out trying to maintain a “rule of thumb” of 10-12 grains of arrow weight for every pound of bow weight. With my 60 lb. Robertson (and I draw about 60 lbs. worth) I should be shooting between 600 & 720 grains for total arrow weight with a high EFOC. I think I’ve thrown the rule of thumb in the ditch but I’m going to be able to maintain the high EFOC.
I really wanted to be able to shoot 2020’s with a 175-grain head (610 grains total arrow weight). It turned out the 2020’s were too light unless I went down to a 125 grain head (566 grains total arrow weight). That brought my EFOC from 15.52% that I was happy with down to 11.11% that I was not happy with. I am able to shoot my old 2219’s (628 grains & 13.68%) but they are a little slow and I would like a higher EFOC.
I took “Fletcher’s” advice (something that was previously suggested by Michael) and tried the 175-grain points in my 2117”s. What a difference. I have no problems with arrow flight even when there is some operator error involved and I’m getting an EFOC of 16.81%. My only concern is that the total arrow weight is only 566 grains (same as lightened 2020’s) so I feel I’ve made some considerable progress there even with the lighter shaft.
And, Bert, you were right about the ‘step’ on the side plate – no more shredded fletching.
Most importantly I feel confident about my shooting and arrow flight.
Thanks very much for all the help guys.
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You’re welcome, Dennis. Also, one thing that I was told at one point on arrow weight, is that the bare minimum you should shoot out of a recurve/longbow is 10 grains per pound of bow weight minus 10%. In other words, for your 60# bow, 600 grains minus 60 grains. I don’t remember who told me this, but if you follow that rule, you should be safe down to about 540 grains with your bow. Just something to ponder on, and something for somebody with more experience and know-how to chime in on. Good shooting and good hunting.
Michael.
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