Bare shafy tuning is very similar to paper tuning, except that it shows more as you shoot longer distances. Another thing is that your form has to be more consistant as there won't be any fletching to correct the shaft. Here's a brief summary of how I've bare shaft tuned over the last 35+ years:
Start at about 6' shooting at a target at shoulder height so you can shoot level. I often kneel down in front of our bag targets at the archery club. It's important to use a target material that is omidirectional so the shaft isn't affected by the target any more than necessary. Straw, excelsior, or bag targets work OK.
Start close and shoot a shaft. Follow Easton's Tuning Guide to reading the shaft and making adjustments. It's sometimes good to make several shots just to make sure the target isn't affecting the arrow. Once you get the shaft entering level and square at 6' then back up to 10 yards or a little less and do the same thing, making finer adjustments as necessary. Then 15 yards; then 20 yards.
Understand that the farther you move back the finer adjustments have to be so as not to over correct for any flaw. You can try tuning this way as far back as your form and shooting ability will allow. I would normally try to get a perfect bare shaft flight out to 35 yards. What you're looking for is a bare shaft that flies like it's lazer guided. All you'll see is a nock going directly away from you.
If you can get it this good then try shooting bare shaftds and fletched arrows together. They should shoot so close to each other that you can't tell a difference. And in most cases broadhead tipped arrows will shoot to the same POI, too.
It can be frustrating. There are a lot of things that can mess you up. Some can be mechanical like cam lean (limb twist), poor cam timing, but most often it will be arrows that are underspined, too little FOC, and others things. It will also show you real quick if your form is off or inconsistant. Grip the bow and all bets are off.
Easton's Tuning Guide covers a lot of this stuff.
If You're Not Living on the Edge You're Taking Up Too Much Space
Martin/Rytera Staff Shooter
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