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-520065-797560Content = blue text00Content = blue text3443605-792480Format = red textFormat = red text1462405-792480Definitions = bold textDefinitions = bold text4966335-797560Rhetoric = green text00Rhetoric = green textStainless Steel and its Many UsesChoosing the Best Barrel for Rifle AccuracyAndrew James DzobaIt does not matter whether one is a Navy Seal, a game hunter, or a recreational shooter, each of these riflemen desire extreme accuracy of his weapon. When selecting a rifle, the barrel is the most important component to consider since a rifle is only as accurate as its barrel. Choosing an accurate barrel for maximum precision is a complicated task as there are many factors to consider: the rifle’s application, the material of the barrel, the twist rate, and the length of the barrel. All of these factors contribute to an effective and precise barrel, but if misconstrued, can lead to a severely inaccurate barrel. The purpose of this manual is to inform the user of the most effective barrel for his intended use. WARNINGS AND HAZARDS OF FIREARMS:Firearms are not toys. Keep guns locked in a safe and away from children atALL times. Keep barrel pointed in a safe direction at ALL times. Always make sure gun is unloaded before taking it apart. List of important terms:Twist rate – one complete revolution of a bullet inside a barrel per so many inches. In a 1:10 twist rate, a bullet completes one full rotation every ten inches.Free-floated barrel – a barrel that does not touch any material of the rifleBarrel length – the length of the barrel where the bullet travels Grain – a unit of measurement for bullets and refers to its mass or weightFPS – feet per secondThere are FOUR major considerations when choosing a rifle barrel:MaterialTwist rateLength of barrelFree-floating barrelMaterialThe optimal barrel material depends on how the rifle will be used. A rifle barrel used for game hunting or target shooting will differ in material from one used for combat or recreation.Game hunting or target shooting:Choose a stainless steel barrelTends to be more accurate because of its malleable properties, making the barrel more preciseWeather resistantLighter weight to carry Combat use or recreation:Choose a chrome moly vanadium barrelStronger and tougher material Extended barrel lifeTwist RateSelecting an effective twist rate is crucial. If the rate is too fast or too slow, it will cause the bullet to destabilize (Petzal, 2010, p. 38).Bullet grains 40 through 55:Select a 1:9 twist rate. A lighter bullet requires a slower twist rate to stabilize the bullet.Bullet grains 55 through 77:Select a 1:7 twist rate. Heavier bullets require faster twist rate in order to stabilize the bullet. Figure 1 is an illustration of a twist rate in a barrel (2013)Length of Rifle BarrelChoose the most effective barrel length. A long barrel equates to greater velocity, but only to a certain extent. According to Mohazzabi and Shefchik (2002), “…initially the muzzle speed increases with barrel length but eventually tends to become a maximum for some optimal length of the barrel” (p. 541). The best choice for barrel length is one that uses all of the powder that propels the bullet, but nothing after that. If there is not enough powder, then the bullet cannot reach maximum velocity.8572527940Figure 2 relates barrel length to velocity, and optimal length of some barrels (2016)00Figure 2 relates barrel length to velocity, and optimal length of some barrels (2016)Barrel length for a 55 grain bullet:Initially, a 20 inch barrel was used to maximize velocity. Currently, a 14.5 and 16 inch barrels are being used by the military for close quarter combat. Keep in mind that a longer barrel does NOT mean a more accurate barrel. Barrel length for a 77 grain bullet (hunting bullet for AR15):Use an 18 or 20 inch barrel to achieve maximum velocity of the bullet.Do not use a shorter barrel, as it does not reach maximum velocity which could potentially wound the animal instead of killing it. Free Floating BarrelChoose a free-floating barrel to build an accurate rifle. This enables the barrel to vibrate freely and not touch any other material, improving accuracy. Having a free-floating barrel means the barrel must:Not touch any material past the receiver (the place where the barrel connects with the rifle)Must be free to vibrate in its own harmonics (naturally)GlossaryFree-floating barrel: This refers to barrels that do not touch any materials of the rifle. It is free to move to its natural vibrationsGrain: 437.5 grains equals 1 ounce. This is used to measure bullet weight.Twist rate: How many inches a bullet travels inside the barrel to complete one full revolution.Works CitedKraus, J. Figure 1 (2013, September 12). AR–15 Barrel Twist Explained. Retrieved July 23, 2017, from , T. Figure 2 (2016, December 15). AR-15 Rifle Barrel Length - Does It Even Matter? Maybe NOT. Retrieved July 22, 2017, from , P., & Shefchik, B. M. (2002, May). The Optimal Length of a Rifle Barrel. Retrieved July 19, 2017, from , D. E. (2010, October). Doing the Twist. Retrieved July 19, 2017, from , D. E. (2012, August). Straight Shooters. Retrieved July 19, 2017, from ................
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