What is the best twist rate for 556?
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 .
Can a 1/8 Twist shoot 77-grain?
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.
What grain 5.56 should I shoot?
When considering military rounds (5.56) you will notice a lot of M193 and M855. Your standard FMJ is going to be the 55 grain M193. This is referred to as “ball” ammo, which generally just means military loading style.
Whats better 1/7 twist or 1/8 twist?
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.
What 5.56 ammo does the military use?
The M855A1, a 5.56 mm Ball ammunition, is an enhanced performance round for today’s combat and training environments. It works with the M4 Carbine, the M249 machine gun, and the H&K and M16A2 rifles.
Is a 1/7 twist barrel good?
A common slow twist rate, for example, could be notated as 1:12. A twist rate of 1:12 means that the bullet does one 360 degree rotation per 12 inches of barrel. A 1:7 twist rate indicates that the bullet will undergo a rotation once every seven inches, which, as you might imagine, is a much faster spin.
What was the twist rate of a 5.56 ammo?
In the 1960’s, when the 5.56×45 and the accompanying AR platform debuted, both rifles had barrels with twist rates of 1:14 inches, or one full rifling twist for every 14 inches of barrel. That’s because at that time the standard choice in 5.56 ammo was a 55 grain FMJ projectile.
What’s the best twist rate for 55 grain bullets?
The 1-in-9 is a great compromise twist rate—not too fast to cause problems with the 55-grain bullets, but fast enough to stabilize all but the heaviest bullets under most circumstances.
What’s the best twist rate for a rifle?
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.
What’s the twist rate for a 16 inch carbine?
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.