We've shot many different kinds of arrows over the years and have developed a real appreciation for carbon arrows. They have come a long way since their inception. Nowadays, carbon arrows are just as good as any aluminum or aluminum/carbon arrows; maybe better. They also provide a toughness and resilience that are hard to match. This makes them a great option for those of us who are tough on arrows.
We always buy the straightest arrows we can afford. We prefer the +/-.001-inch straight arrows because consistent accuracy is important. We like hitting what we are aiming at, and we don't like "hoping to get lucky."
However, not long ago we purchased a dozen +/-.001-inch straight carbon shafts and discovered something disturbing. We built the dozen arrows and once we started shooting, found one of the arrows wouldn't group with the rest. At 20 yards, it would hit six inches different than the other 11. We checked the straightness, and it was straight. So, we went on to check spine, nocks, fletching, etc. Everything seemed to be fine.
Frustrated, we decided to move the straightness indicator on our arrow checker to the very end of the arrow. We were amazed at what we found. When we checked the arrow for straightness in the middle, it was indeed +/-.001-inch. But when we checked the nock end of the arrow it was +/-.009-inch! The whole arrow was straight up to last inch and a half of the nock end. And that inch and a half was bent.
If the nock end is .009-inch out of alignment, then the whole arrow might as well be .009-inch crooked. It did us no good to buy the better arrows and then put our nock in a crooked end.
We went on to check the whole dozen arrows. They were all +/-.001-inch straight in the middle, as the manufacturer advertised. But, at the ends of the arrows, there was quite a variance.
When we called the manufacturer and told them about the bent ends on the arrows, they said they measure for straightness only on the middle 28 inches of the 32-inch shafts. They also said that outside that 28-inch span, there might be some slight variance. The manufacturer suggested cutting an even amount off both ends of the arrow. So, if we wanted a 28-inch arrow, we should cut two inches off each end of a 32-inch shaft.
Not only did we not know this, but a few of the dealers we talked to had never heard of this either. Nor was this information provided in the arrow-building instructions from the manufacturer. Normally, when the arrows are cut to length, the extra is always cut off the point end. The nock end is often already fletched and not really available for trimming. That means that our nocks end up being inserted into the bent ends. And, the nock end is the worst possible place for the arrow to be bent. That means, during the shot, the string isn't pushing straight behind the arrow.
Since then, we have checked many different brands of carbon arrows and found that they all seem to have issues with the ends being straight. The first and last couple inches are often bent to some degree compared to the rest of the shaft.
Because we liked a lot of the overall characteristics of carbon arrows, we didn't give up on them. As suggested, we started cutting even amounts off both ends of the shafts. The results have been great. To this day, we still use carbon arrows, and now that we know how to cut them, they are a lot straighter and more accurate than they were before.