Perhaps you have been checking out sporting rifles like the AR 15 and you came across some interesting accessories like a specially designed AR 15 gas block. This strange looking device can be located on the scope rings and may include a rear sight or rails. But what exactly does it do and should you think about buying one? Let’s look a little closer at gas operated weapons to explain.
What is a Gas Operated Rifle?
Gas operation refers to a reload mechanism. For example, early rifles had a simple reload mechanism. This was all done by the operator of the weapon. However, as rifles advanced, multiple shot weapons came into being. For example, the Winchester repeating rifle had a lever the shooter flipped and this expelled the spent cartridge and reloaded the chamber. This was a huge advancement over single shot weapons, but as firearm technology advanced, faster reload times were needed, so the semi automatic rifle as invented.
When you fire a gas operated semi automatic rifle, here is what happens as you pull the trigger. The powder in the cartridge explodes and releases pressurized gas. This provides the necessary energy to eject the used cartridge and chamber a new one.
Redirecting the Gas
As the gas escapes the cartridge, it is redirected to the area designed for ejecting and reloading. On an AR 15 this is done with the AR 15 gas block. Because the gas block is on the front, many rifle owners choose to buy gas blocks with an optional front sight, and one which flips up or down is very important if you plan to use a scope sometimes. This will keep the front sight out of the way until it is needed.
Gas Ports
All gas operated weapons have a special port in the barrel. This is what lets the escaping gas into the gas block, so it can be redirected. The size of the port is very important because too little gas will not allow the weapon to reload automatically and too much could generate an explosion or damage the internal parts. In fact, in some rifles, gas ports may become enlarged with wear and this can be remedied by using an adjustable AR 15 gas block.
If you are customizing your AR 15, you can choose from a number of gas blocks. Some have rails and others are low profile. Depending on the needs of the shooter, these accessories can be very useful.
