1-in-8 Inches Twist Rate For a 16-inch general-use carbine, the 1-in-8 twist is about as versatile as it gets. This twist rate will comfortably stabilize bullets up to 80-grains, and the excellent 75- and 77-grain bullets also work great at a wider spectrum of velocities — which means barrel length isn’t critical.

Most modern AR-15 barrels will come in three twist rates: 1:9, 1:8, and 1:7. The 1:9 barrel is best for stabilizing lighter and mid-weight bullets between 45 and 77 grains. The 1:8 twist barrel is the most versatile of the bunch, the perfect option for16-inch carbine AR-15 (the most common configuration on the market.)

75’s and 77’s are your go to for magazine fed bullets and longer range shots. The 1/7 will stabilize them for sure. 55 grain and 62 grain FMJ’s are perhaps the lowest quality bullets available.

The lower the number of the twist, the faster the twist rate or the faster the bullet will spin. Generally, fast twist barrels are used for longer bullets while slower twist barrels are used for shorter bullets.

The best barrel twist rate depends on what type of bullet you are shooting. A fast twist rate such as a 1:7” twist barrel will work better with long-range modern bullets where as a shorter twist such as 1:10” or 1:11” twist barrel will work better with shorter bullets.

The short answer is that barrel twist starts the bullet spinning at a given rate to stabilize the bullet. An increasing twist rate will have little effect on accuracy except in the most extreme cases. However, a decreasing twist rate will almost certainly result in a dramatic decrease in accuracy.

Yes, a 1 in 7 barrel will shoot 55 Gr bullets well. As stated, the 55 Gr FMJ is not the best for accuracy, but a good barrel will shoot decently with the better ones, such as the Hornady.

The muzzle velocity difference between a fast and slow twist is virtually zero. But too fast a twist can spin bullets too fast, and, with bullets more unbalanced more than others, the centrifugal forces they have will pull them off the muzzle axis when shot; accuracy gets worse.

daved. Your comment echoes what I’ve heard from other sources – for the the 6.5x47L using 130’s, 8.5 is optimal. Presumably that twist works better with the higher velocity with that bullet weight. Using that logic, 8.5 twist might work with the 139-142 bullets but the 8 twist would be more appropriate.

Keyholing is the result of bullet instability. At very short range, some bullets are not stable and will keyhole while they will stabilize farther out and leave round holes. The most common causes of keyholing, though, are worn or no rifling, bullets unsuitable for the rifling twist, wrong size bullet (.

“The problem with ‘over-stabilizing’ a bullet (by shooting it from an excessively fast twist rate) is that the bullet will fly ‘nose high’ on a long range shot. The nose-high orientation induces extra drag and reduces the effective BC of the bullet.”

Rifling refers to the spiral grooves that are cut into the internal surface of a gun barrel. Rifling helps impart a spinning motion to a bullet when it’s fired. A spinning bullet is much more stable in its trajectory, and is therefore more accurate than a bullet that doesn’t spin.

Extremely high velocity can cause bullet problems with fast twist barrels because of the inertia of the bullet not wanting to rotate causing engraving issues and in extreme cases jacket separation from the core. The heavier the bullet is at the same velocity, the worse the problem.

The bullet can blow up. It can only spin so fast before the centrifugal force is so high, it will fly apart. If a 52 grain 223 bullet comes out of a 1:7″ twist barrel at 3000 feet/second, the bullet is spinning over 308,000 revolutions per minute.

To stabilize such projectiles the projectile is spun around its longitudinal (leading to trailing) axis. The spinning mass creates gyroscopic forces that keep the bullet’s length axis resistant to the destabilizing overturning torque of the CP being in front of the CM.

The 1:9, 1:8 and 1:7 are popular twist rates that will stabilize most . 223/5.56 ammunition. The 35- to 60-grain bullets made for AR-15 rifles have ballistic coefficients of . 109 to .

What is twist ratio and why is it important? Twist ratio is the number of twists per meter or foot of wire pairs. It is important because the number of twists per foot in a pair of wires translates to the more resistant the pair will be to cross talk or noise.

Does Twist Rate Make a Difference in Velocity? Yes. Our tests show that, with the 80-90gr bullets, a 1:10 or 1:12 barrel will give you as much as 80fps more velocity than a 1:8 barrel, shooting the exact same loads. Fast twist (1:8) barrels have more drag and friction, which can slow the bullet down.

Anytime you increase the twist rate, all else being the equal, pressures will increase.

The smooth bore rifle will have a higher velocity. Rifling slows the bullet down (energy is transferred to a direction other than “forward”), that’s for sure, but remember the purpose of rifling: to stabilize flight.

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1. AK-47 Rifle. Most peoples on earth know the word ‘AK-47’ a most effective and accurate weapon, designed by Mikhail Kalashnikov in 1946-1948 from the Soviet Union.
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8. 1903 Springfield.

The spin imparted by rifling significantly improves the stability of the projectile, improving both range and accuracy. Typically rifling is a constant rate down the barrel, usually measured by the length of travel required to produce a single turn.

5R reduces projectile deformation as it passes through the bore during the firing sequence. More uniform projectile means better accuracy. Secondly, by sloping the transition to the groove, the barrels become much easier to clean.

Button rifling is an older method that has proven itself over the years. It provides normally better than average accuracy. Single point is the slowest and most difficult method but done properly results in the highest quality barrel.

For that reason, the faster twist barrels—1:8 and 1:7—are best with heavy bullets. 1:8 twist barrels will stabilize bullets up to 80 grains, and 1:7 tubes will actually stabilize heavy, long-for caliber, aerodynamic bullets up to 90 grains.

The 5 R’s: Refuse, Reduce, Reuse, Repurpose, Recycle.

Answer: The 5 R’s – reduce, reuse, recycle, recover and residual management. Reduce, reuse, recycle, recover and residual management. – Five actions that can make your organization and you a better steward.

Bright and shiny with well defined rifling grooves is what you want in an ideal case but few milsurps will be that perfect. A little darkness, a little frosting as described indicates some corrosion.

Polygonal barrels- Glock uses this. The entire bore is shaped like a polygon. 5R- Canted land rifling, common proflie done by Obermeyer, Bartlein, Kreiger, and others.