What does barrel twist mean

Or, to put it in a write-in-your-notes version:. You see, no gunsmith or firearms enthusiast worth his or her salt can just let things be by deciding the most efficient turning rate for all rifles and calling it a day. A common slow twist rate, for example, could be notated as A twist rate of means that the bullet does one degree rotation per 12 inches of barrel.

A twist rate indicates that the bullet will undergo a rotation once every seven inches, which, as you might imagine, is a much faster spin. There are a wide variety of bullet weights available, anywhere between 30 and 80 grains, in the extremes of the 5. Most modern civilian sporting rifles will never see combat.

This is one reason private citizens have access to AR-style rifles with a variety of twist rates. Most modern, short-barreled ARs come in three basic twist rates: , , and If you want a mil-spec rifle, the barrel runs ammo loaded with a 62 grain projectile like a dream.

This rate of twist can also handle even heavier bullets up to a hefty 90 grains. The twist barrel is the most versatile of the bunch. This twist rate gives you the most flexibility, effectively stabilizing projectiles up to 80 grains but not over stabilizing lighter ammunition. The barrel is best for stabilizing lighter and mid-weight bullets ranging between 45 and 77 grains.

These are rough guidelines. Of course, If you want to dig really deep into the details, we suggest this Twist Rate Stability Calculator devised by the folks over at Berger Bullets. When it comes to handguns and hunting rifles, the rate chosen by the rifle maker is usually appropriate for the intended cartridge. There are some exceptions, but the differences in accuracy and performance will be minimal.

A slower rate may produce slightly less pressure and deliver slightly better accuracy when paired with lighter projectiles in each caliber.

These slower twist rates are also generally sufficient to stabilize heavier projectiles, particularly when targets are within practical hunting range. The only reason you might need a faster twist rate in a hunting rifle would be for shooting extremely heavy projectiles at targets beyond yards. For this reason, snipers and long-range marksmen could benefit from a faster rate of twist. Twist rate is just one factor that affects shooting accuracy.

As always, the best way to improve your shooting is to send lead downrange. However, understanding twist rate and applying that knowledge can help you fine tune shooting performance. Finding the right combination of barrel twist and bullet weight may be the fine detail that takes your shooting to the next level. Let your fellow shooters know — share this article using the Facebook, Twitter and other social media icons below. The more we all know, the better organized and stronger the shooting and hunting community will be.

The Lodge AmmoToGo. Look for tips for the range here. Decreasing the twist rate is counterproductive and destabilizes the projectile. With this sort of rifling, the projectile is progressively spun up to the final twist rate.

Plus, current manufacturing processes and tolerances are quite impressive, already delivering excellent performance. The length, diameter, shape and velocity of a given projectile determine the twist rate that best stabilizes it in flight. Shorter higher-caliber read: larger-diameter bullets tend to require slower twist rates, while longer, smaller-caliber bullets require higher twist rates. Our earlier examples highlight this, with the fat. However, end users utilize a variety of different types of ammunition in their firearms; so usually it makes sense to optimize specifically not for a single projectile but rather for a range of different types of bullets.

So what happens if the twist rate is too high or too low? When the projectile is not spun quickly enough, it may not be sufficiently stabilized in flight; then it begins to yaw and tumble, destroying its accuracy. On the other hand, excessive twist rates can affect accuracy, accelerate wear and even rip jackets apart and cause projectiles to disintegrate. The popularity of the AR platform and the wide variety of different. Anyone who decides to build up their own upper will need to decide between an array of barrel choices.

Consider the range of ammunition you intend to use for your specific applications, and choose a barrel configuration to match. Ever wonder how those rifling grooves can be made so precisely? Some common methods for producing rifled barrels include the following:. Grab a cleaning rod, jag and patch.