How To Measure A Recurve Bow String

Article past Marvin Long – Sep 20, 2006
Measuring Traditional Bows and Bowstrings

There is a lot of misconception most measuring bowstrings for traditional (conventional) bows and I would like to help alleviate some of the questions about these bows and bowstrings.

I take sat on the AMO (Archery Manufacturers System) & ATA (Archery Trade Association) Specifications commission for some twenty years and have been involved in many discussions well-nigh archery equipment specifications. I have likewise been manufacturing bowstrings commercially for 28years. I fabricated my commencement bowstring in Boy Scout Military camp in 1954.

Recurve and Longbows are historic items that are now being used more and more than, which I am glad to encounter. Archers using the old manner equipment will aid keep live the history of our sport.

Ben Pearson, Earl Hoyt, Fred Acquit and others that where involved in our sport in the middle of the concluding century and earlier, understood at that place needed to exist standards set for the industry to make it easier for archers to enjoy the sport. Setting a standard for measuring the bow I am sure was one of many and since the compound has become much more dominate in the sport, many of the newer sport shop operators are not as familiar with the traditional bows.

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 cord groove to string groove effectually the curve of the bows limbs, not straight from tip to tip. This measurement does not go into the bend of the handle merely across theface of the bow limbs from string groove to string grove. This will requite yous 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 exterior of each peg. ATA Specs say that a bow should be properly braced with a string that measures 3″ shorter than the bow. Then if a bow is 60″ is should be braced properly with a string measuring 57″ under 100 lbs of tension later on 20 seconds. Bowstrings for bows of less than xl lbs should be measured in the same fashion, using 50 lbs of tension.

Bow Makers used a Bowstring Principal Fix of steel cables that would be designated as AMO (now ATA) Bow Lengths such as AMO 66″ (bowlength) merely 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 Principal Set would range from 45″ to 69″ and would brace bows from 48″ to 72″.

A Dacron Bowstring, which will stretch near an inch under100 lbs of tension, volition await "out of the package" like it is 4 inches shorter than the bow. This is the reason y'all hear people speak about bowstrings being 4inches shorter than the bow length. This will only be for a Dacron bowstring and not under tension or actual length.

Because all materials stretch differently, measuring everything under pressure compensates for the differences between materials.The newer materials, similar Fastflight practise not stretch like Dacron, then they will expect longer out of the package and more like the three inches according to ATA Standards. Strings are supposed to be measured with out any twist at that time.Notwithstanding strings are installed with some twists to give ameliorate performance and past twisting and archer can attain better pointer flight. Some mod archers shoot with equally many as 50 twists in a seventy″ bowstrings. To get the proper length bowstring later on twisting 50 twists you may have to get-go with a bowstring one″ longer.

Strings that accept been shot a long time and need to exist changed will probably wait longer than when they were new so going by the bow length is a more consistent starting reference.

Strings tin be twisted to change their length and this tin be done to alter the bow ready upwardly so it performs ameliorate for each private archer. This will assist get better flight characteristics for the arrow; this is called tuning your setup or getting all parts working all-time together.

Marv Long measuring the Carry Grizzly AMO 58″, the ruler does non go into the handle but goes directly across the confront of the limbs.

Shows the AMO 58″ bow measures 57″ from cord groove to cord grove.

Show 4 bows of dissimilar ages. The left bow is marked AMO 58″ the adjacent bow is marked 60″ and the remaining two are not marked for length. They are all Bear Archery Bows The 3rd bow is a static recurve with the aluminum lamination and a running acquit logo, The 4th bow is a laminated bow signed by Nel's Grumley with no weight or length on information technology.

Shows the bow is marked equally an AMO 58″ bow and this bow measures 57″ from string groove to strings groove but being an AMO St233andard it volition brace properly with a 55″ AMO bowstring so it is a AMO 58″ bow.