To test a rear bag, shoot 10 rounds without it and 10 with it, with the same rifle, at the same distance and from the same position, then measure how far each hole is from the center of the bull. Average those distances for each string and compare: in our test, shots landed 28% closer to the bullseye with Sling Steady under the stock. Muzzle rise was about 75% lower. It also helps manage recoil.
It takes one range trip, two bulls, a ruler and a calculator. Here is how to do it so the result means something.
What you need
- One rifle and one load. Don't change ammunition between strings.
- Targets with a clear center and a printed ring of known size on each bull. We used Birchwood Casey Big Burst.
- A rear bag. Sling Steady is a rear shooting rest bag that sits under the stock, and it rides on your sling or attaches directly.
- A marker, a phone camera and a ruler or tape.
Set up the test
- Pick one distance and keep it. We shot at 105 yards. Anything from 100 yards out works, as long as both strings are at the same distance.
- Pick one position and keep it. Prone off a bipod is the easiest to repeat. Whatever you choose, use it for both strings.
- Use a fresh bull for each string, and label each one by hand before you shoot it: your name, and "no bag" or "bag".
- Confirm zero first. You are testing where the shots land against your aim point, so the rifle should already be hitting where you aim.
Shoot the two strings
- No bag first. Fire 10 shots at the "no bag" bull with your normal rear support: your fist, your hand on the stock, whatever you use now.
- Then with the bag. Put the bag under the toe of the stock and fire 10 shots at the "bag" bull. Let the rifle settle, relax the support hand and use small squeezes for elevation.
- Same pace both times. Don't rush one string and take your time on the other.
If two people can shoot it, run it for both. Our test used two shooters on the same rifle.
Measure distance from center
- Mark each hole. Circle every hole with a marker so none gets missed or measured twice. Ten shots should give you ten holes.
- Measure each hole. With the ruler, measure from the center of each hole to the center of the bull. Do it on the paper, or on a photo taken straight on.
- Use the ring as your unit if you measure on photos. Measure the printed ring's diameter in the same photo and divide each hole's distance by it. Then photos taken from different distances still compare evenly. That is how we did ours.
- Average each string. Add the 10 distances and divide by the number of holes.
- Compare. Percent closer = (no-bag average − bag average) ÷ no-bag average × 100.
Read the result honestly
Distance from center and group size are different measures. Group size, the spread between the two widest holes, tells you how consistent the string was. Distance from center tells you how close the shots landed to your aim point. In our test, distance from center improved for both shooters, while group size got smaller for one and slightly larger for the other. Report what you measured, not more.
Ten shots is a small sample. If you want more confidence, repeat the test on another day and see whether the result holds.
Our result
Two shooters, the same AR-platform rifle, 105 yards, 10 shots without the bag and 10 with it. Average distance from the bullseye went from 0.64 to 0.46 ring diameters. That is 28% closer to the bullseye with Sling Steady under the stock. David landed 28% closer, with hits in the center X going from 1 to 4. DJ landed 29% closer, with hits inside the inner ring going from 3 to 5. Results vary. The targets are in our 105-yard test.
Run it with ours: the Pro 9" for bolt-action, sport and hunting rifles, or the Sport 7" for AR-platform rifles. $89.99, ships filled with SteadyFill.
Related reading: Why rear support makes you more accurate · Range day: bench and prone
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