I am just starting out with archery. I am preparing to be able to archery hunt deer next season. Can I use the same arrows for both bows. My draw length is 25". I have the following: - Blackout Intrigue Compound (New) set at 43# for my 25" Draw using a Whisker Biscuit rest and - Martin Jaguar (used / new string) @ 28" #40, 60", using a arrow rest similar to "Saunders Archery Express Rest". I tested the draw using a scale @25" draw, I got 34# The Martin came with Gold Tip Expedition 5575 arrows @ 31"; as near as I can figure, these have a .400 spine. Can I use these arrows with both bows for practice purposes? I cut one arrow down to 27" just to see how it feels. From what I understand this would change the spine "stiffness". Is there a way to figure the spine strength / stiffness when an arrow is shortened?
Your info on the spine of Gold Tip 5575 arrows is correct, they are a 400 spine. At your stated draw length and poundage, a 400 spine arrow is considered too stiff of a spine for your setup. I only looked at a compound bow spine chart, but a 600 spine arrow is ideal for your current specs. With that being said, an overspined arrow is fine to use for practice purposes, there are no safety concerns like if an arrow was way underspined. Since the 5575's are so stiff for your setup they may fly better if you leave them at their full length of 31". The shorter you cut an arrow the "stiffer" it acts. In a situation where the spine is too stiff, the following may help weaken the spine: leaving the arrows full length, increasing bow draw weight, adding tip weight to the arrow (front of arrow). I don't know what poundage you may be working towards for hunting, but I would caution you to check your State's hunting requirements for minimum poundage allowed for deer hunting. Here in Idaho where I live it is required to have a minimum draw poundage of 40 lbs to hunt deer.
Thanks for the information. Washington is similar to Idaho "minimum of 40 pounds of pull measured at 28 inches or at full draw". The Gold Tip 5575 arrows are for the Martin Jaguar (recurve bow). I am considering replacing the limbs with "ILF 50 or 55# limbs". I will do this only so I have "backup" in case something goes wrong during the season. So, I plan to practice with both, but I will primarily hunt with the compound bow. My Blackout (compound bow) has a different set of arrows. They were .400 spine at their full length, and then cut to 26" with the bow set at 43#. This was done when I purchased the bow and arrows. So based on the above info, these arrows are now overspined. What effect does an overspinned arrow cause? How do I determine the correct arrow stiffness for my setup? After I get used to the weight and become a proficient Archer / Toxophilite (google, lol) I plan on increasing the draw weight to 50#.
Well then, hello neighbor. I live in Lewiston, right on the border with eastern WA. Clarkston is right across the Snake River from me. I will go into some detail below but want to say this first. As a brand new shooter, do not get too caught up in perfect arrow spine and tuning for a while. A really big part of "tuning" is controlled by the way the shooter themselves shoot the bow. In other words, I could tune my setup to be "perfectly" tuned, but then hand the bow, arrows, and the same release aid to you and it would not show "tuned" when you shot it. Even if we were both the exact same draw length. How the person shooting the bow holds it and sets off the shot is a huge part of the "tune". A new shooter needs to develop their shooting form to a point that it is repeatable before tuning will not just be a very frustrating experience. 400 spine arrows, at 26" long, and at 50 lbs of draw weight, are not that far off on spine for you with a compound bow. Especially with some extra tip weight added. A 150 grains of tip weight on that setup would put you right on the cusp of a 400 spine arrow on a chart. I use the Gold Tip chart mainly. If you go to the Gold Tip site and then click on "learn" on the far right at the top of their home page, a drop down will show up that has several options, one of them being a spine chart. There are 3 spine charts, one for traditional (recurve), one for compound bows rated under 330 fps IBO, and one for compounds rated over 330 fps IBO. The fps IBO ratings are in reference to the bows actual IBO speed rating, not the actual speed your setup is shooting out of the bow. For your question about how spine effects arrow flight, it is about how the arrow flexes as the energy from the bow is applied to it. It needs to flex consistently and return to its original position. Generally, too weak of spine will favor going to the right and too stiff of a spine will favor flying to the left. Too much of either one can cause inconsistent arrow flight, so you'd never be able to shoot very good groups. I think 400 spine with a 125 grain tip will fly well enough for you to practice with to learn repeatable shooting form and see some decent groups as you get better. The recurve may be a different story, but I think they'll be fine with the compound. If, after you have shot for a while, you still can't get good groups, then add some more tip weight to see if that helps.
Thanks neighbor, fair points above. I will start sending arrows down range and focus on my anchor, form and release. Right now I have 125gr Field Tips and a couple of 125gr broad tips. I guess like everything else, starting up a new interest will cost a few $$ just to get established. It's good that I have 8 months to budget it out.
