If you are looking to upgrade your bow for the coming season, or get into that first bow to take advantage of an extended season, read on young Robin Hood to get the latest information.
Was your current bow designed and built before the Nixon administration? Are you tired of hearing your buddies talk about the benefits of solo cams versus dual cams, reflex versus deflex and following the conversation about as well as a college dissertation on nuclear physics? If you are looking to upgrade your bow for the coming season, or get into that first bow to take advantage of an extended season, read on.
A lot has been written about cams (or wheels) over the years. The different styles, shapes and individual features are numerous, but they generally can be narrowed down to five distinct types: round wheels, soft cams, hard cams and single (solo) and the 1.5 hybrid cams. Each has its own set of characteristics that dictates its best application.
If you gauge the different features in terms of speed, it is easy to rank them from slowest to fastest (round wheel, soft cam, with hard cam, solo cam and the hybrid cam being very similar), but this tells only part of the story. In addition to speed, other factors that make an archer choose a particular cam over another are comfort, tunability, quietness and accuracy.
Round wheels, as noted above, are the slowest of all the cams, but they are still with us today for a reason; they are arguably the most accurate, as well as the most forgiving of all the cams and work extremely well for finger shooters. They are reasonably quiet, vibrate very little and are easy to tune. Their slower speed and pinpoint accuracy make them a favorite for fixed-distance target shooters. Due to their rainbow-like trajectory, their popularity has faltered in hunting applications.
Soft cams are about the slowest cams many hunters opt for. They have many of the advantages of a round wheel, but they generate enough speed to make them adequate for many hunting applications. They are still quiet, stay tuned relatively well and are forgiving even for finger shooters.
Hard cams (or hatchet cams as they are sometimes called) are the fastest of the dual cams. While they create blistering arrow speeds, they have several major disadvantages for the hunter. First off, they are harder to keep tuned than any of the other cams, due to their propensity to stretch strings and buss cables. They also can be loud and need to be dampened considerably. They are also the hardest to shoot accurately and the least forgiving. However, if you are an expert archer, and enjoy tuning a bow, the speed may outweigh the inconvenience of occasional tuning.
Solo cams (or single cams) are a single hard cam matched to a round idler wheel. Their popularity has been such a success that virtually every bow manufacturer today produces a solo cam bow. They are very easy to tune since there is only one cam that rolls over. They are also extremely quiet and as fast as any dual cam on the market.
The 1.5 hybrid cams are the newest style of cam on the market. They are a combination of both a dual cam and a solo cam. The speed of the hybrid cam is similar to that of the solo and hard cam. The main advantage of the hybrid cam is that it essentially elimates nock travel, which is found on a solo cam. It functions the same as a solo cam where the idler wheel is replaced with another cam. The addition of the second cam offsets the movement of the nock as compared with a solo cam.
The ins and outs of cam let-off and adjustability
Regardless of which type of cam you decide works best for you, there are several things to pay attention to when selecting the exact model of bow/cam. Thankfully, most of today’s bows are adjustable for draw length, but how adjustable they are and with what amount of difficulty are two important questions that need to be answered. It is always smart to have your draw length measured before buying a bow. If you change your shooting style or grow a bit (in the case of an adolescent), draw-length adjustment becomes imperative.
Let-off is another cam function that needs to be understood to effectively tailor a bow to your needs. Let-off is expressed in a percentage and on many of today’s bows the let off is adjustable between set parameters (65%-80%). For simple math, let’s assume that you have a 100-pound bow (not realistic — just simple). At peak weight, you will have to pull 100 pounds, but after the cams "roll over" and fall into the let-off valley, you will be holding 35 pounds with a 65% cam; with an 80% cam, you would be holding only 20 pounds. Different states have different regulations on how much percentage of let-off is allowed for hunting. If you have a chance of encountering a trophy, you should stick with a 65% let-off bow. For the trophy to be eligible for its appropriate place of honor in the Pope and Young Archery record books, the maximum let-off allowed is 65%.
Risers (the handle part of the bow) come in different shapes, designs and materials. Their construction and design greatly influence the price, function and performance of the bow.
Like cams, they have many subtle differences, but the three main styles are reflex, deflex and straight.
Reflex risers are easily spotted as they curve away from the natural curvature of the limbs (see photo). This design produces faster speeds as it reduces the brace height (distance between the string at rest and the center of the riser) of the bow.
Deflex risers are the exact opposite of a reflex. Instead of curving away from the limbs, they follow the curvature of the limbs. This increases brace height and creates a slower arrow speed (all things being equal) but are more forgiving to shoot and are generally more accurate for shooters (especially for a shooter with less-than-perfect form).
Straight risers fall somewhere in between (they are technically a reflex riser, just much less so than some of the radical reflexes on the market). They are reasonably fast, forgiving and consequently can be found on many current production hunting bows.
The material construction of a riser affects the cost, the weight and the size (grip diameter) but does not really affect the performance, accuracy and longevity of the bow. There are two basic ways that risers are constructed: cast (aluminum, magnesium), and machined (aluminum). Risers also are constructed with carbon fiber, but these are not nearly as common as the two previously mentioned methods/materials.
Cast risers are every bit as strong, accurate and reliable as machined and can be had at a fraction of the cost. The only disadvantages are in size and weight. Generally speaking, cast risers are thicker in the grip section and heavier than machined risers.
Machined risers are the lightest (for metal) of all the risers and have a smaller grip that tends to fit most hands better than a cast riser, but they are also more expensive to produce.
Carbon-fiber risers are lightest of them all, but they are at the top of the price ladder.
Speed Rating IBO vs. AMO
There has been a lot of confusion over bow speeds in recent years, as manufacturers all vie for the top spots on the velocity charts. In an attempt to keep the playing fields level and give consumers a basis for comparison, two rating methods have been adapted. IBO (International Bowhunters Organization) and AMO (Archery Trade Association, formerly the Archery Manufacturers and Merchants Organization) are the two standards used to compare speed. While they are standard, they do differ drastically from each other.
AMO speed is figured using a bow set up at 60 pounds of draw weight, 30 inches of draw length and using a 540-grain arrow.
IBO speed is figured using an arrow that weighs 5 grains for every 1 pound of bow weight. Example: a bow set at 70 pounds of draw weight with an arrow that weighs 350 grains (70x5).
As you can see, the rating system is drastically different for each method, which explains the wide spread in velocities between AMO and IBO speeds. IBO is using a higher draw weight, a drastically reduced arrow weight (compared to AMO) and an undisclosed draw length (longer draw lengths translates to more speed). Since many archers have a "need for speed" attitude, it is obvious why bow manufacturers choose to advertise the IBO speeds of their bows but for the best comparison AMO is a more consistent litmus test.
Which Bow is For You
Selecting the right bow is a personal thing, and the decision will depend a lot on what you will be doing with it. Before you start narrowing down the selections first ask yourself; will you be hunting from a treestand or ground hunting? How large of game are you going to pursue? At what distance will the average shot be made? How much weight can you effectively handle? How good of an archer are you (honestly)?
Only after you answer all of these questions can you effectively narrow down the selection of bow. As an example, take a look at my buddy John. He is 6 feet tall with a normal build. He has shot a bow a bit, but this will be his first bow purchase. He is going to be hunting whitetails almost exclusively from a treestand, but wants to take a trip out west next year for a Rocky Mountain elk hunt. What bow would work best for his needs?
To start with, he is going to need an easy-to-shoot bow. Being his first bow, he is going to have a learning curve to go through and the more forgiving the better; however he still needs power, relative speed and preferably in a small, lightweight package. Bows, like most things in life are a series of compromises. To get speed you often increase noise. Compact sizes usually decrease accuracy (specifically they are hard to shoot well) - but are a big advantage to treestand hunters.
What I would recommend a reflex (to straight) riser design, coupled with a solo cam. He would want the power of a 70-pound bow for elk but could tune it down to the low 60’s for practice and whitetail hunting. A short axle-to-axle length would be nice for treestand hunting and carrying up steep hills and through brushy draws, but it is not as necessary as accuracy and speed (especially for the walking and stalking elk hunt). If he could afford it I would suggest a machined riser over a cast riser to get the smaller grip and lighter weight. With it narrowed down that far it is now up to style, price and name brand.
As you can see, by understanding the different features of a bow and applying them to your specific hunting conditions and need, selecting the right bow for the job is not that difficult.