The Archery Trade Association (ATA) specifies that a Traditional Bowstring should be labeled and sold by the length of the bow not the bowstring length itself. A 60" Bowstring is for a 60" bow, not the length of the bowstring. A Traditional bow is measured from string groove to string groove around the curve of the bows limbs, not directly from tip to tip. This measurement does not go into the curve of the handle but across the face of the bow limbs from string groove to string grove. This will give you the approximate length of the bow. A Bowstring for bows over 40 lbs is measured by placing it over steel pegs and stretching it at 100 lbs of tension for 20 seconds. The measurement is taken from the outside of each peg. ATA Specs say that a bow should be properly braced with a string that measures 3" shorter than the bow. So if a bow is 60" is should be braced properly with a string measuring 57" under 100 lbs of tension after 20 seconds. Bowstrings for bows of less than 40 lbs should be measured in the same manner, using 50 lbs of tension. Bow Makers used a Bowstring Master Set of steel cables that would be designated as AMO (now ATA) Bow Lengths such as AMO 66" (bow length) but it would have an actual length of 63" under 100 lbs of tension. If this cable should brace a bow correctly it would be classified a 66" bow. A Bowstring Master Set would range from 45" to 69" and would brace bows from 48" to 72". A Dacron Bowstring, which will stretch almost an inch under 100 lbs of tension, will look ‘out of the package’ like it is 4 inches shorter than the bow. This is the reason you hear people speak about bowstrings being 4 inches shorter than the bow length. This will only be for a Dacron bowstring and not under tension or actual length.
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