It occurred to me that in the two and a half years I’ve been writing here, I’ve never really touched on the use of a shooting sling. Sure, I’ve talked quite a bit about the various slings I’ve tried, but never how the sling actually helps the shooter increase precision.
If you are relatively new to shooting, your primary exposure to rifle slings will come from the tactical and hunting arenas where they are used mainly to carry weapons. Some of the newer designs feature easy to use adjustments that help cinch the sling closer to the body to free up the hands, or to loosen the sling for easy transition to the back, shoot with the opposite shoulder, or use some other carry method. Quick adjustable slings are primarily retention tools that can be used to aid in precision in a pinch by tightening them into the shoulder pocket. This will meet the needs of most shooters just fine. But, if you have the time to take advantage of a true shooting sling, you will see a great improvement in your marksmanship.
Shooting slings (as opposed to tactical slings) are designed to help mitigate the primary enemy of good marksmanship stability: the support elbow. The general principle of all rifle positions is to adopt a good bone-on-bone position and relax into it in such a way that there is no muscle involved in supporting the weapon. Without a sling, there is always a weak link with the supporting arm. When the elbow is rested on a stable surface such as the ground or knee, the arm will be bent and the hand will be forward of the elbow in a type of open-ended triangle. As the shooter relaxes into position, gravity will do its thing and want to make the triangle open up by pushing the hand forward and the rifle down. The only way to counteract this is to use muscle tension, which inherently introduces variables.
Essentially, a shooting sling closes the open triangle by connecting the front of the rifle to the top of the arm (above the bicep/tricep). With this connection made, muscle is no longer required to support the rifle. As a bonus, a tight sling will pull the stock of the rifle deeper into the shoulder and result in a tighter lockup.
As a side note, be cautious about going *too tight* with a sling unless you are wearing heavy layers. A very tightly cinched sling will induce pulse jump in the sights.
Here are four of my shooting slings representing different design philosophies. From top to bottom: Riflecraft RS2 (attached to my M1), Turner Biothane 1907 sling, TAB Gear Sling, and a Short Action Precision Positional Sling.
While I spend the most time with the Short Action Precision, all of these slings do effectively the same thing. Each of them is adjusted to a desired carry length for moving about with the rifle. Once you need to take a shot, you insert your supporting arm through the shooting loop until the loop is above the bicep, cinch it down, wrap the supporting hand behind the forward sling mount, take aim, and fire. Realize that the amount of length needed for the shooting loop is different for each shooting position. Generally, you can use the same shooting length setting for kneeling, sitting, and squatting. Prone will probably require more slack, since your body is no longer upright. Here is a great demonstration by Jacob Bynum of Rifles Only with a modern shooting sling (directly comparable to my SAP). While this is a modern sling, the principles remain the same.
The differences between the pictured slings come down to adjustability. The TAB and Riflecraft slings are meant to be set to a single carry length with a “general purpose” shooting length (most likely sitting or kneeling, since prone shots in the field are rare), and then out the door you go. The 1907 sling is designed to be field adjustable with the metal claw hooking into the holes at the desired length, but it is comparatively slow. It was meant to serve as a carry strap outside of conflict, but the doctrine at the time presumed the soldier would hook into the shooting loop prior to engaging in battle, and then stay “slung up” until the fight was complete. The SAP sling is the most quickly adjustable, with loops that are pulled and released to quickly adjust shooting length for each position (this is why I prefer it over the others for my practice sessions).
Using a shooting sling should be somewhat uncomfortable, but the tighter you get the lockup the better your precision will become. I am generally a 2-3 MOA shooter from the sitting while using a sling, and 5-6 MOA without it.
Another factor to consider when using a sling is how the rifle will be carried. Modern methods, particularly for carbine carry, involve slings that loop around the shooter’s back. Most shooting sling designs will not work this way since there will be too great a difference between the carry length and shooting length of the sling. There are exceptions, though, and they usually involve a length of very tough bungee material.
For shooting slings, the traditional method of carry is over one shoulder with either the rifle on the shooting side shoulder with the muzzle pointing up (American style), or on the support side shoulder with the muzzle pointing down (Rhodesian, or African, style). There is a third one taught at Gunsite called European carry, but I personally don’t see any benefit of it over the other two. Here is a short video explaining each of these carry methods.
Which one you choose is ultimately up to you and your personal preference.
You can use modern adjustable tactical slings as shooting aids as well. There are two methods to doing this. By cinching down the length adjustment and otherwise using correct shooting form, you will help stabilize the rifle by a good amount. It is not quite as good as a true shooting sling, but it will work well enough for most people when speed is of the essence. This really only works well if you have a sling attachment point at the forward end of the handguard, where a traditional sling might be attached. If you mount it close to the receiver, you might have trouble creating the right amount of tension. For this reason, most of my carbines have two QD sling points: one near the receiver and one near the end of the handguard. I like to have options.
Some modern tactical slings with the quick adjusting loops can be pressed to serve as a makeshift shooting sling as well. For instance my FTW sling creates a sizable loop when the adjustment carriage is moved forward. I can take advantage of this loop and put my arm through it in a pinch. It does not cinch down and hold position like a traditional shooting sling would, but it works well enough for a shot or two.
Not all slings do this, though. My BFG Padded VCAS, when adjusted to have a large enough loop, has far too little space between the back of the loop and the front sling point. Despite that, it can still be used with the first method (tightening the carry length and pulling the rifle into the shoulder pocket).
Slings are an important part of good marksmanship, but one that is often ignored. Most of the training I see people doing revolves around very close range and very fast engagements. The practical marksman should be thinking a bit further out than that, and should use all tools available.