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    • kjlarson
        Post count: 26

        What is the reason for cutting an arrow to something close to your draw length? I have a bit more than a 30″ draw and don’t bother cutting them anymore leaving the shafts at 32″. When practicing I am shooting a mix of shorter and longer arrows. Knowing this, I may be compensating, but I can’t say that I really have any obvious problems.

      • Stephen Graf
        Moderator
          Post count: 2428

          30 inches is a long draw!!! Remind me of that if we ever get into a bar fight so I can run 😯

          In general, a longer arrow will give you better flight and a more forgiving shot (and a better sight picture in my opinion). With aluminum and carbon, it is no problem using longer arrows. With wood, it is sometimes hard to get the spine right with longer lengths. Especially if the bow weight is high.

          So leave ’em long. And shoot straight.

        • John Carter
            Post count: 71

            Length is simply one element of tuning,,,no length will provide better flight or forgivness than another simply due to length,,,they need to be in tune with the bow and that alone will decide how well they fly.
            A longer length can give you some advantage in aiming if your a concious gaper or point of aim shooter.

            I like my arrows to be within one inch of my shelf so that’s one of the things I choose my static spine and point wheights on.

            I also like all my arrows to be the same,so I don’t mix an match arrow lengths or wheights.

            99% of my shooting is in club or competition field archery or 3D,with maximum distances 60 and 35 yards respectively,,so I like all my arrows within a given set to be the same.

            I have different sets for different competition and I have different sets for hunting,I can certainly tell the difference between them.

            If I break arrows I have a couple of different ways of recovering them,,but I don’t mix lengths or wheights.

          • Stephen Graf
            Moderator
              Post count: 2428

              John Carter wrote: Length is simply one element of tuning,,,no length will provide better flight or forgivness than another simply due to length,,,

              All else being equal. A longer arrow is more forgiving than a shorter arrow.

            • John Carter
                Post count: 71

                Sorry Steve, but mate your going to need to quantify that before I buy it.

                The way I see it “all things being equal” there’s not going to be any difference at all for the simple fact both arrows would be in perfect tune.

              • kjlarson
                  Post count: 26

                  I will add that all my practice is done at 15, 20 and 25 yard from above, below, and level. My target is on a hillside. My goal is to get within 20 yards of my elk or deer. If I estimate it to be greater than 20, I pass. It amazes me how much more drop I get at 25. For my practice target, that is fine. I just won’t risk it on an animal.

                • Frank H V
                    Post count: 129

                    I like about 2″ of arrow beyond my draw length. The reason is simple, & important. When I hunt I use a broadhead & I don’t want a sharp broadhead near my fingers on the bow. My reason is if I get excited & draw a bit longer than normal, I’ve got a cushion between my tender fingers & a sharp broadhead. :wink
                    Frank

                  • Stephen Graf
                    Moderator
                      Post count: 2428

                      John Carter wrote: Sorry Steve, but mate your going to need to quantify that before I buy it.

                      The way I see it “all things being equal” there’s not going to be any difference at all for the simple fact both arrows would be in perfect tune.

                      Here’s an experiment you can try that will illustrate the inherent stability of a longer arrow : place the butt end of a 6 foot stick on your palm. Now let go of it and keep the stick from falling. You will find this fairly easy to do. Now use a shorter stick, and shorter stick. Eventually you will not be able to balance it at all.

                      The ease with which you can balance the stick is proportional to the distance between your palm and the center of mass of the stick. The closer the center of mass is to your palm, the harder it is to balance the stick.

                      To prove this to yourself, take a stick that you almost couldn’t balance and add a weight to the end of it. Now try to balance it again with the weight end up in the air. Now you will find that you can balance the stick easily again. this is because the center of mass has been moved away from your palm.

                      Finally, now that you have experience with what it is like to balance sticks, try holding your arrows in the same way. A long one and a short one. Even if there is only 2 inches difference in length, you will find that it is easier to balance the longer one.

                      What this translates into when shooting a bow is forgiveness. If you can make a perfect shot every time, then use whatever arrow you want. But if you are inclined to screw up (like me), then you will appreciate a forgiving arrow.

                    • Brad
                      Member
                        Post count: 35

                        [quote=”Steve Graf Here’s an experiment you can try that will illustrate the inherent stability of a longer arrow : place the butt end of a 6 foot stick on your palm. Now let go of it and keep the stick from falling. You will find this fairly easy to do. Now use a shorter stick, and shorter stick. Eventually you will not be able to balance it at all.

                        The ease with which you can balance the stick is proportional to the distance between your palm and the center of mass of the stick. The closer the center of mass is to your palm, the harder it is to balance the stick.

                        To prove this to yourself, take a stick that you almost couldn’t balance and add a weight to the end of it. Now try to balance it again with the weight end up in the air. Now you will find that you can balance the stick easily again. this is because the center of mass has been moved away from your palm.

                        Finally, now that you have experience with what it is like to balance sticks, try holding your arrows in the same way. A long one and a short one. Even if there is only 2 inches difference in length, you will find that it is easier to balance the longer one.

                        What this translates into when shooting a bow is forgiveness. If you can make a perfect shot every time, then use whatever arrow you want. But if you are inclined to screw up (like me), then you will appreciate a forgiving arrow.

                        Steve,
                        Not arguing here, just don’t understand…

                        I understand your experiment, but how does it translate to the arrow being shot out of a bow? As an example, I draw 28″ on a longbow. If I have an arrow cut to 29″ BOP, which is spined perfectly for a given bow, and have another one cut 32″ BOP, which is also spined perfectly to that bow, how is the 32″ arrow more “forgiving”? If anything I would think the longer one would be less stable, as it would take it slightly longer to come out of paradox [given more space between it’s center-point and the ends of the shaft… or am I way off base here?

                      • William Warren
                        Member
                          Post count: 1384

                          Not trying to answer for Steve but the center of mass would represent the arrow’s spine. Take 2 identically spined arrows the same length and cut 2 inches off of one and now the center of mass has moved closer to the bow and now they are no longer identical in mass or spine. The shorter arrow will be stiffer. My question is: which one will recover from paradox quicker? My guess is the one that experiences less paradox? But which one?

                        • Brad
                          Member
                            Post count: 35

                            I would agree Duncan, but I thought what they were talking about was two different length arrows that were both spined perfectly for the same bow [as opposed to two identically spined shafts that you cut different lengths].

                          • Stephen Graf
                            Moderator
                              Post count: 2428

                              Brad – you are right. We are talking about two arrows that are both spined correctly for the bow.

                              The center of mass is that point about which the mass is balanced. So if you balance the arrow on a knife blade, the balance point is the center of mass.

                              If both arrows are spined correctly, that means that they flex around the bow in such a way that their trajectory is directly at the target and they are not deflected by the handle.

                              So, as I mentioned before, if you make a perfect shot with either arrow, it will fly perfectly to the target.

                              But… If you don’t make a perfect shot. If you torque the handle, or drop the bow, or pluck the string, etc… The longer arrow will tend to be less affected and continue on its intended path and hit closer to the mark than a shorter arrow.

                              To demonstrate this, take the long stick again. This time hold the end of it in your hand and “aim” it at a target and throw it. Now try the same experiment with a much shorter stick, again holding it by the very back. You will have a much harder time getting the shorter stick to the target.

                              In short, the longer the distance between the string (point of thrust) and the arrow center of mass, the more forgiving the arrow will be when shot. Duncan basically said this when he observed that the closer the center of mass is to the handle, the more stable the arrow flight will be…

                              We have talked too much about this. It is very easy to test. Just take a full length arrow and a short arrow. Tune ’em up and then shoot them 10 times each. Measure your groups. I am betting the longer arrow will give you a better group. 😀

                              If not, then you will be by definition, a much better shot than me (not that great a claim to fame 🙄 ). For it means you have perfect form.

                              It’s like shooting a bow with very low brace height. It is well established (I hope) that a high brace height is more forgiving. But if you are a great shot, then it doesn’t matter what the brace height is. For you will always shoot well. But for a poor shot like me, I need all the help I can get, so I try to tease as much brace height out as I can…

                            • Brad
                              Member
                                Post count: 35

                                Thanks for the exlanation Steve, although I’m still not sure I get it (evidently physics is not my strong point!).

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