The bullet is deliberately oversize relative to the bore so that the jacket will engage the rifling and impact a spin. If you donвЂ™t believe me, try hammering one through a bore with a wooden dowel sometime. It takes a lot of work to jam a bullet through a barrel. At this point, there is nothing that is making the bullet move faster. At some point, the rate of volume increase will exceed the rate of pressure increase.

Think of the space as the inside of a tube that gets longer and longer. But in a rifle barrel, the volume available constantly increases as the bullet moves down the bore. In a fixed volume environment, as long as the burn reaction continues, pressure will build. However, barrel length also comes into play. Certainly, the powder charge type and burn characteristics will have a major impact on how long pressure continues to increase. There are two big factors that impact the velocity of a bullet in Barrel Length:ДЇirst, in a perfect, frictionless environment, as long as the pressure behind the projectile is increasing, the bulletвЂ™s velocity will also increase. WeвЂ™ll try that in comparison to a 16-inch model too.Д«efore we get into testing, some background info is in order. ThatвЂ™s an Aero eight-inch 300 AAC Blackout barrel. Oh, you might notice a fourthВ one in the photo. With just one вЂњjust for funвЂќ exception, weвЂ™ll stick to non-SBR barrels that are available without the need for sending Uncle Spendy extra cash for tax stamps: 16вЂі barrels, 18 barrels, and 20 barrel inches. So, in the context of recreation and defensive use, letвЂ™s take a look at the impacts ( or possibly lack thereof) of choosing from the most common length barrels. Just to set the stage, weвЂ™re talking about service rifles here, not fancy bench rest stuff where competitors have to call their shots for either the right or left eye of a mosquito or other ectoparasite at distances of 800 yards. Will General вЂ Mad DogвЂ™ Mattis ever compete on Dancing With The Stars? Here, weвЂ™ll explore the answer to these, and more, important questions.

Most accurate 4 inch barrel 9mm auto