June 6th Shooting Day!!!

Shooting day is almost here. clean your weapons, count your ammo, and let destroy some targets.

Contact me with any questions.  Every man for themselves for lunch this time.

Long Range Rifle Shooting--Precision vs Accuracy

We wanted to start on a relatively simple topic relating to precision rifle shooting before diving into a technical discussion on ballistic coefficients and how to factor in the Coriolis Effect. Let’s start with an understanding of “precision” and “accuracy” and how they relate to each other. There have been many articles and books written about the subject so we just want to use this as a simple introduction into more topics. What is accuracy? For precision shooting, accuracy, in general, is whether you are able to hit the target or not—the target being the measured value. If you are able to get on target, you are shooting with a certain degree of accuracy (assuming you were aiming at the target).

What is precision? Precision would be better described as the repeatable consistency of your shots. That is, how close each shot is to one another. The degree of precision is not relative to the point of aim, necessarily, but to the impact point of each shot.

What we are trying to describe here is that a shooter can be precise but not accurate, or the shooter can be accurate but not precise. The objective is to achieve both.

Let us relate this to target shooting. Assume you have a standard target with a center bulls-eye and expanding concentric rings.  Our measured value being relative to the center point of the bulls-eye at the center of the target. If you impact the target within any ring you can say you are accurate enough to hit the intended target.

Now, assume you shoot 10 rounds consecutively, aiming at the center of the target, and all 10 rounds hit in the upper left hand corner of the target. Since your point of aim was at the center of the target, this represents a low degree of accuracy; however, since the10 rounds shot had close impact points relative to each other, this represents a high degree of precision. The key is to have that level of precision at the point of aim, or center of the bulls-eye. This combines precision with accuracy.

 

Figure 1 – Accuracy vs Precision

 

When it comes to precision rifle shooting we need to understand what will affect the accuracy and precision of our shooting. These will all be topics we dive into deeper as we continue on in the blog series. These topics include fundamentals of marksmanship, rifle set-up, caliber selection, atmospherics, and many more.

The fundamentals of marksmanship are always important but many times overlooked or even forgotten. You will find that the fundamentals and atmospheric conditions are some of the largest variables to long range precision shooting.

Construction and specifications of the rifle are also important: barrel contour and length, twist rate, stock selection, bedding type, and muzzle break will have an influence the level of accuracy and precision. The optics (i.e., scope) and how it is mounted will also play a role in bringing together precision and accuracy. The caliber and cartridge of the ammunition will influence the ballistics (i.e., how the bullet travels through the space between the muzzle and the target), which will have a role on accuracy and precision.

The rifle construction, optics, and ammunition are variables we can control (depending on budget constraints), but the environment is often a variable that we cannot control.  As precision rifle shooters we need to understand how environmental factors influence the ballistics of the bullet during its flight path.  This will include air pressure, wind, temperature, inclination, etc.   Finally, these variables are interrelated, and will influence the other variables.   

Bottom line, as we begin to shoot and continually fine-tune our skills, consistency and repeatability is what we strive for. We can go out to the range, send a bunch of rounds down range and hit the bull’s-eye once in a while. The objective, however; is getting to the point that we can repeatedly hit the bull’s-eyes every time—not only in practice but under pressure, stress, and varying environmental conditions. As you build your skills and dip your toes into competitive shooting you will see how stress and time pressure can throw everything out of whack. The key is to make sure that you gear is set and locked down so that you remove the variable of your gear out of the equation and focus on the fundamentals of marksmanship that will always be tested under stress.

I hope this gives you some food for thought around precision rifle shooting. Stay tuned for the next article in the series where we will talk about equipment set up. Till them stay safe and keep shooting.

Make Sure You Are Blowing the Right Amount of Gas!!!

When building an AR your barrel length is one of the main choices. When you choose your length, you have to make sure that you also choose the right gas block tube length too. The gas blocks come in many different lengths. 

The shorter your gas system, the higher the pressure it's has. The bolt and carrier are slammed harder; they work harder. Plus, a shorter gas system is harsher in operation, because it cycles in a shorter time.

Rifle length is the original system that the gas system is designed around. With a rifle length, an aluminum gas block is fine, which makes the rifle lighter. With a carbine length, the pressures almost double, and an aluminum gas block will eventually wear down by the hot gas. You should use a steel gas block system on carbine length  or mid-length rifles.

 As the gas systems get shorter, the size of the gas port needs to get bigger, because they need to bleed off more pressure in a short time. If the gas port is too small, the rifle will short-stroke, causing feeding problems.

On the other hand, if the port is too big, the rifle will be "over gassed."  Which will send the gas to interact with the bolt too early,with the shell still in the chamber and will cause it NOT to eject.

An over gassed rifle will be really difficult and uncomfortable to shoot.  This cart will help you get a better idea of the relationship between the distance of the gas block and the pressure.

Look at the chart below:

Gas System                         Gas Port Location                                  Pressure (PSI)

    Pistol                                            4.7"                                                   48,000

    Carbine                                       7.8"                                                   33,000

   Mid-Lenght                                  9.8"                                                   26,000

     Rifle                                           13.2"                                                  19,600

    

Next Shooting Day!!!

Our next shooting date is June 6th @ BC

We have been waiting for this shoot along time.  Get your sights zeroed, because we got a 200+ range that day.

Let's do it!!!

Contact me for any questions