Mechanical Advantages. 

 There is an impressive difference in both output and ease of use when using a compound bow versus a recurve bow. The benefit from the cams is that it allows the shooter to have a greater draw string therefore allowing the arrow to be pushed faster. a good recurve bow with a large draw weight (force required to draw bow) will fire at about 175-220fps (feet per second) while a compound bow of equal draw weight would be able to shoot anywhere from 270-380fps an increase of almost 200%. The cams also allow the shooter to pull back an immense amount of weight but when at full draw it is reduced by about  75-80% of original required effort or "let off". so a draw weight of 70lbs with a let off of 80 percent only requires the user to hold 14lbs of force to keep the arrow at full draw. this is extremely handy when hunting because the hunter may need to hold the bow at full draw for a minute or longer before he get a clear shot. without the cams then you would be forced to hold that 70lbs until you released.

The figure to the left shows arrow drop for 6 different shooting bows. as you can tell there is a significant arc required to hit a target at 30 yards with a slow shooting bow. whereas a faster bow has less drop.











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