I was recently asked by a Recurve student about whether barreled shafts should be set up the same as parallel shafts with regard to centershot. He commented that some expert archers are saying barreled shafts should be lined up with the string (actually the string plane) but parallel shafts should be lined up with the point peeked out from behind the string (the “standard” recommendation for “fingers” shooters). So which way should barreled shafts be set up?
I answered “yes.”
Having the arrow point peeking out from behind the string is the traditional setup position. Let’s look at this. The reason that the arrow point is set up outboard from the string plane is because when a finger shooter releases the string, the string slides off of the fingers (actually the string pushes the fingers out of the way, but “action-reaction” applies: as the string pushes the fingers away, the fingers push the string away). Since the fingers curl in toward the archer’s head, the string slides toward the archer slightly as it slides toward the bow. The bow pulls the string back toward the string plane as it pulls the string back toward the bow and the string slides over to be inside the plane of the bow and then back outside. The nock separates from the string when the string is at a peak in this sideways oscillation (away from the bow, similar to where it started), at least if it is properly tuned it does. The force on the arrow from the string is directed mostly down the shaft and by having the arrow point slightly outboard of the theoretical string plane, then the point end and nock end of the arrow are aligned when the arrow separates from the string. This results in the force being more down the line of the shaft (in which direction the shaft is very strong) and not sideways (in which it is weaker). Force that goes into the arrow oscillation/flexing doesn’t move it toward the target. If you want to see this in action, there is a YouTube video in which a bloke shot a weak arrow with ever stronger bows and the amount of side-to-side bending gets extreme, almost bizarre, before on the final shot (weak arrow-strong bow) the arrow shatters from the side force. (Note: this is why a spine match is so important for “fingers” archers.)
The argument goes that a barreled shaft is thinner toward the point and when it slides forward to the central thicker section, it moves the arrow point out to the left (for a RHed archer) anyway, so starting from that position gives you twice as much offset and a misaligned force going down the string.
So, is this right?
Yes, sort of … the arrow at brace is sitting fairly close to the thicker center section and so this position is built in, it doesn’t sit with the thinner part on the arrow rest in the position the centershot is set in. When the arrow is drawn, the thinner part slides in toward the bow.
Does it make any difference?
Probably not … for most archers … here’s why.
The position of the arrow rest, which determines the position of the arrow when it is sitting on the arrow rest (the so-called centershot position), is a setup position. When a bow is initially set up, you put things as close to where they will be when the bow is tuned as you can. Why start with wild setup positions which will make tuning that much harder? But since those final positions are determined a great deal by your technique, there is no way to specify exactly what they will be without you participating. So, the described positions are positions that seem to be close … for most archers.
The final position of the arrow rest … and the nocking point, and the brace height, and myriad other settings on a recurve bow should all be determined by tuning tests. If your arrow rest is set so the arrow point peeks out from behind the string (when viewed properly: from behind with the string and limbs free) and you think you might benefit from having the arrow lined up in the string plane because you shoot barreled shafts, then by all means test this out.
Be sure to document your bow before you make any changes. Then measure something that determines the quality of your shots (group size, practice round scores, etc.) and then change the centershot and test again. If these metrics improve, keep the change. If they do not or things get worse, set it back to the position you began with.
Realize that elite archers know their equipment better than most archers. They may have starting positions they use for their bows that are very, very close to what they will be when tuned in. Most archers need to learn more before they will know what to expect, so minute information gathered from the elites is probably of not much value.
Also realize that there are many, many variables involved in tuning a recurve bow to a high level: nocking point, string material, string diameter, serving diameter, nock size, the archer’s tab, the brace height, the limb alignment, the stabilizers, nock size, … <pant, pant, pant> … , the quality of the limbs/riser, the button position, the button pressure, … , as I said, myriad things affect the tune. Interestingly, a good basic set up of a recurve bow gets you 90-95% of the way to where you will be at the end. Tuning takes a great deal of time and a great deal of effort for that last 5-10% of performance. We are saved because of a basic rule which is: you can’t tune any better than you shoot, so for most archers, little tuning is needed. Since the elites shoot so well, they have to tune the heck out of their bows. They are, after all, looking for the last fraction of a percent of the performance they can get from their equipment and the law of diminishing returns applies.