Post by BT on Feb 14, 2006 20:00:00 GMT -5
Thread by LockMaster
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HOW TO CHOOSE A BOW
Most of the bows today are fine pieces of equipment. Manufacturers have improved the bows to a point where breakage is not a problem unless you are trying to shoot super fast with light arrows. All of the bows, from the least expensive to the most expensive will probably shoot more accurately than you. You need to look for features that suit you and the way you are going to use the bow. Here are some features to consider in your purchase.
Bow Length - The trend today is for very short bows. You have to shoot a release aid with these bows and they won’t work for you if you have a long draw. Longer bows tend to be more forgiving. Some may argue with that statement, but look at the archers that shoot the indoor targets where they don’t just shoot for bulls-eyes. They shoot for the x in the center of the bulls-eye. The winners are shooting bows that are at least 48” long. Short bows are handy in tight situations, like hunting from a blind.
Bow Weight - The trend is very light weight bows. A light bow is nice if you are packing it all day on long hunts. Light bows tend to not be as accurate as a heavier bow. Most target shooters use heavier bows and add stabilizers. More mass is more stable. Check out target rifles. They all have heavy barrels. More mass also absorbs vibrations better, although there are a number of products on the market now that do a good job of absorbing vibrations.
Brace Height - This probably influences accuracy and speed more than any other feature. Brace height is the distance from the string to the grip of the bow. A lower brace height gives a longer power stroke so the arrow absorbs more energy and is faster. A low brace height also keeps the arrow on the string longer so any irregularity in your form has more of an effect on the arrow. Bows with a brace height below 7” tend to be a little tricky to shoot for hunting.
Cams - The larger aggressive cams give more speed. They also are harder to draw. There is not much difference in drawing a 70 lb. smooth cam and a 60 lb aggressive cam. Arrow speed will also be similar. You can’t get more out of a bow that you put into it.
One or Two Cams - Throw out the advertising hype and they both do the same thing. Timing on an aggressive 2 cam bow is critical. Timing isn’t near as critical on a soft 2 cam bow. Timing is the roll over of the cams. They need to roll over at the same time. The nocking point will travel up or down if one cam rolls over before the other. The nocking point will move more with a radical cam with big lobes. Timing is not much of a problem with the newer 1 cam bows so they can have aggressive cams. There was nocking point movement on the early 1 cam bows. You also can have nocking point movement with a 1 cam bow because the nocking point is not in the center of the string, like on a 2 cam. You have twice as much string above the nocking point as below because the string goes over the idler wheel and back down to the cam. String stretch will move the nocking point. How much string stretch you get depends on the string material. Newer bow string materials don’t stretch much after a few hundred shots.
Bow Draw Weight - Today’s 50 lb bows will kill just about any animal you will hunt in North America. Don’t get a heavier bow weight than you need. You should be able to draw the bow straight back without raising the bow or having to put a lot of effort into it. You need to be able to draw a bow in slow motion after you have been sitting on a stand in cold weather for several hours.
Draw Length - Most people today have too long of draw length. They try to pick up speed by increasing the draw length. That causes tension in the muscles which reduces accuracy and causes target panic. You should be comfortable at anchor when pulling into the wall. That is especially true with the short valleys on bows today. Creep just a little while you are aiming and you are out of the valley and holding the peak weight of the bow. That can cause you to trigger the arrow and hopefully it doesn’t fly into the next county.
INFLUENCES ON SPEED
Speed is based on the stored energy of the bow and arrow weight. Some bow features store more energy than others. Here is list of the items that control speed and the approximate speed you can gain.
Peak Weight - A change of 5 lbs. of peak weight is equal to about 10 f.p.s.
Draw Length - An inch change of draw length is equal to about 10 f.p.s.
Arrow Weight - A change of 25 grains of arrow weight will equal about 5 f.p.s.
Brace Height - An inch change in brace height is equal to about 5 - 10 f.p.s.
These are rough estimates because many times if you change one you have to change something else. For example, increase the draw weight or draw length and you might have to shoot a stiffer arrow, which is heavier. You also get diminishing return as you reach the extreme. Increasing the draw weight from 85 to 90 lbs will not have as much affect as increasing it from 45 - 50 lbs because the percentage of change.
In addition to this, some bows use the stored energy more efficiently. Needle bearings in the cams will reduce friction and increase speed. Limb design can also make a difference in efficiency. Others like the type of cable slide, string material, peep sight, etc., also make a difference.
ADVERTISED SPEEDS
Manufactures advertise AMO speed and IBO speed. AMO is the Archery Manufactures and Merchants Organization. IBO is one of the largest 3-D shoot organizations. AMO speed is with a 540 grain arrow shot from a 60 lb. bow with a 30” draw. IBO uses a 70 lb. bow and a 350 grain arrow because that is the lightest arrow and heaviest bow allowed in their shoots. The speeds the manufacture list are likely to be faster than you will shoot. Most bows come with an adjustable draw length. 30” draw may be obtained with 3 different cams that cover 3” of draw adjustment. Those 30” draw lengths will all have different speeds. Some manufacture’s draw lengths run long so what they call 30” may actually be 30 3/4”. That will increase the speed rating by up to 5 f.p.s. In addition to all of that, many test their bows with no nocking point on the string because that additional weight on the string will reduce speed by a couple of feet per second. Use the manufacture’s rating as a rough guide. They may vary by more than 8 f.p.s. from an independent test. 5 f.p.s. would not be noticeable to anyone shooting a bow. It generally takes 10 - 20 f.p.s. to make any noticeable difference. You can figure bows that are within 5 f.p.s. speed rating are equal because of the differences in their testing.
_________________
If you always do what you've always done, you will always be where you've always been.
___________________________________________
HOW TO CHOOSE A BOW
Most of the bows today are fine pieces of equipment. Manufacturers have improved the bows to a point where breakage is not a problem unless you are trying to shoot super fast with light arrows. All of the bows, from the least expensive to the most expensive will probably shoot more accurately than you. You need to look for features that suit you and the way you are going to use the bow. Here are some features to consider in your purchase.
Bow Length - The trend today is for very short bows. You have to shoot a release aid with these bows and they won’t work for you if you have a long draw. Longer bows tend to be more forgiving. Some may argue with that statement, but look at the archers that shoot the indoor targets where they don’t just shoot for bulls-eyes. They shoot for the x in the center of the bulls-eye. The winners are shooting bows that are at least 48” long. Short bows are handy in tight situations, like hunting from a blind.
Bow Weight - The trend is very light weight bows. A light bow is nice if you are packing it all day on long hunts. Light bows tend to not be as accurate as a heavier bow. Most target shooters use heavier bows and add stabilizers. More mass is more stable. Check out target rifles. They all have heavy barrels. More mass also absorbs vibrations better, although there are a number of products on the market now that do a good job of absorbing vibrations.
Brace Height - This probably influences accuracy and speed more than any other feature. Brace height is the distance from the string to the grip of the bow. A lower brace height gives a longer power stroke so the arrow absorbs more energy and is faster. A low brace height also keeps the arrow on the string longer so any irregularity in your form has more of an effect on the arrow. Bows with a brace height below 7” tend to be a little tricky to shoot for hunting.
Cams - The larger aggressive cams give more speed. They also are harder to draw. There is not much difference in drawing a 70 lb. smooth cam and a 60 lb aggressive cam. Arrow speed will also be similar. You can’t get more out of a bow that you put into it.
One or Two Cams - Throw out the advertising hype and they both do the same thing. Timing on an aggressive 2 cam bow is critical. Timing isn’t near as critical on a soft 2 cam bow. Timing is the roll over of the cams. They need to roll over at the same time. The nocking point will travel up or down if one cam rolls over before the other. The nocking point will move more with a radical cam with big lobes. Timing is not much of a problem with the newer 1 cam bows so they can have aggressive cams. There was nocking point movement on the early 1 cam bows. You also can have nocking point movement with a 1 cam bow because the nocking point is not in the center of the string, like on a 2 cam. You have twice as much string above the nocking point as below because the string goes over the idler wheel and back down to the cam. String stretch will move the nocking point. How much string stretch you get depends on the string material. Newer bow string materials don’t stretch much after a few hundred shots.
Bow Draw Weight - Today’s 50 lb bows will kill just about any animal you will hunt in North America. Don’t get a heavier bow weight than you need. You should be able to draw the bow straight back without raising the bow or having to put a lot of effort into it. You need to be able to draw a bow in slow motion after you have been sitting on a stand in cold weather for several hours.
Draw Length - Most people today have too long of draw length. They try to pick up speed by increasing the draw length. That causes tension in the muscles which reduces accuracy and causes target panic. You should be comfortable at anchor when pulling into the wall. That is especially true with the short valleys on bows today. Creep just a little while you are aiming and you are out of the valley and holding the peak weight of the bow. That can cause you to trigger the arrow and hopefully it doesn’t fly into the next county.
INFLUENCES ON SPEED
Speed is based on the stored energy of the bow and arrow weight. Some bow features store more energy than others. Here is list of the items that control speed and the approximate speed you can gain.
Peak Weight - A change of 5 lbs. of peak weight is equal to about 10 f.p.s.
Draw Length - An inch change of draw length is equal to about 10 f.p.s.
Arrow Weight - A change of 25 grains of arrow weight will equal about 5 f.p.s.
Brace Height - An inch change in brace height is equal to about 5 - 10 f.p.s.
These are rough estimates because many times if you change one you have to change something else. For example, increase the draw weight or draw length and you might have to shoot a stiffer arrow, which is heavier. You also get diminishing return as you reach the extreme. Increasing the draw weight from 85 to 90 lbs will not have as much affect as increasing it from 45 - 50 lbs because the percentage of change.
In addition to this, some bows use the stored energy more efficiently. Needle bearings in the cams will reduce friction and increase speed. Limb design can also make a difference in efficiency. Others like the type of cable slide, string material, peep sight, etc., also make a difference.
ADVERTISED SPEEDS
Manufactures advertise AMO speed and IBO speed. AMO is the Archery Manufactures and Merchants Organization. IBO is one of the largest 3-D shoot organizations. AMO speed is with a 540 grain arrow shot from a 60 lb. bow with a 30” draw. IBO uses a 70 lb. bow and a 350 grain arrow because that is the lightest arrow and heaviest bow allowed in their shoots. The speeds the manufacture list are likely to be faster than you will shoot. Most bows come with an adjustable draw length. 30” draw may be obtained with 3 different cams that cover 3” of draw adjustment. Those 30” draw lengths will all have different speeds. Some manufacture’s draw lengths run long so what they call 30” may actually be 30 3/4”. That will increase the speed rating by up to 5 f.p.s. In addition to all of that, many test their bows with no nocking point on the string because that additional weight on the string will reduce speed by a couple of feet per second. Use the manufacture’s rating as a rough guide. They may vary by more than 8 f.p.s. from an independent test. 5 f.p.s. would not be noticeable to anyone shooting a bow. It generally takes 10 - 20 f.p.s. to make any noticeable difference. You can figure bows that are within 5 f.p.s. speed rating are equal because of the differences in their testing.
_________________
If you always do what you've always done, you will always be where you've always been.