When it comes to the discussion of recoil, the usual issue is how to reduce it. Recoil, or more specifically the anticipation of recoil, is the usual cause of flinching – a shooter’s worst enemy. Flinching occurs when a shooter anticipates recoil and, often unconsciously, jerks the trigger. Reducing recoil can often aid the shooter in concentrating more on the fundamentals of marksmanship and less on reacting to the gun’s recoil.
On more practical terms, recoil can get downright unpleasant. Heavier calibers can produce enough recoil to make the shooting experience less than fun. Reducing recoil can put the fun back into a trip to the range.
Reducing recoil also reduces wear and tear on the gun, extending its life. For semiautomatic pistols, less recoil means slower slide velocity, and less battering of parts.
In some circumstances you might want to increase recoil. For example, more recoil might help the gun to cycle more reliably. Reliable cycling can also be regulated by spring strength in semi-automatic pistols. For pistols with compensators, more recoil, or to be more specific, more gas pressure, might be desired to make the compensator work more effectively in reducing muzzle climb.
Several factors influence recoil, including bullet weight and velocity, and gun weight and design.
Another factor that affects recoil dramatically is the burning rate of the gunpowder. Handloaders have a real advantage here since they can select a gunpowder with a desired burning rate to regulate recoil.
Bullet weight
All else being equal, specifically the same gunpowder and charge weight, lighter bullets produce less recoil. An important feature of this axiom is that the gunpowder is the same for both bullets. Using different gunpowders for heavy and light bullets changes the whole issue on recoil. With different gunpowders you could end up with more recoil for the light bullets than for the heavy bullets. The gunpowder issue is discussed in more detail farther down this page.
Gun weight
The heavier the gun, the less the recoil. This assumes the same gun design. Different gun designs can change the felt recoil (see below). Adding weight to a gun can reduce recoil. One common addition to a 1911 pistol is a full-length recoil spring guide rod to replace the common, short version. The weight of the full-length guide rod is ideally placed as well, being at the front of the gun, which helps to dampen muzzle flip. Some gun makers offer full-length guide rods as standard equipment on some models. Some parts manufacturers also offer tungsten full-length recoil spring guide rods. Tungsten is much heavier than steel and adds approximately one more ounce than a steel full-length guide rod.
One concern that competitive shooters have is whether the extra weight, especially of the tungsten guide rods, at the front of the gun makes it feel sluggish when transitioning from one target to another. Most (but not all) shooters don't think so, and the author has not found that to be the case either. A more experienced opinion can be found at Brazos Custom Guns.
Gunpowder Burning Rate
The burning rate of a gunpowder can affect how much recoil is produced. Generally speaking, faster burning gunpowders produces less recoil than slower burning gunpowders.
Different gunpowders burn at different rates. People often put them in categories like fast, medium, and slow. However, there are no clear boundaries for these categories since the burning rates form a continuum from fastest to slowest. Burning rate charts can be found at several locations on the web (for example: Ramshot Powders, Reload Bench, Vihtavuori Loading Guide). However, there is no clear agreement on the ranking of many gunpowders because the ranking for any given gunpowder varies depending on who made the chart. Therefore, burning rate charts should be used as guides and not as gospel. Never estimate gunpowder charges based on their ranking in a burning rate chart. Always follow a loading guide.
Principles
Okay, in very simplistic terms, here is the logic behind how the burning rate of a gunpowder influences recoil.
1.
Faster burning gunpowders reach peak pressure more quickly than slower gunpowders. Consequently, a smaller charge weight is required for faster gunpowders to reach a given velocity.
2. By inference, slow gunpowders require more of it (usually weight) to reach a given velocity.
3. More gunpowder means more gas. More gas produces more recoil.
4. Therefore, slower gunpowders require more of it to reach the same velocity, and they produce more gas which results in more recoil.
Okay, let me put that in English. When comparing gunpowders with different burning rates, the faster burning gunpowder will produce less recoil when propelling the same bullet to the same velocity. An important feature is that the weight of the gunpowder required to achieve the same velocity is less for the faster burning gunpowder (see box).
Let me give an example to illustrate this point. Let’s say you have two gunpowders, a “fast” one and a “slow” one. Let’s say that the fast gunpowder requires 5.0 grains to propel a 130 grain bullet at 1000 fps, and that the slow gunpowder requires 6.0 grains to propel the same bullet at the same velocity. According to the logic outlined above, the fast gunpowder should produce less recoil.
The difference in recoil between a fast and slow gunpowder can be huge! The difference in recoil between two gunpowders with a similar buring rate can be small, but still noteworthy.
Ultimately, you have to test for yourself which gunpowders will produce the least recoil for your needs. But here is a real world example. I tested two gunpowders made by Winchester: 231 and Super Target. Both of these powders are considered fast burning and both produce light recoil. Opinions vary on which is the faster burning of the two. I tested them to see which might produce the least recoil with one of my favorite bullets, the Remington 147 grain FMJ Match bullet (available at Midway). It takes 4.5 grains of Winchester 231 to launch that bullet at 950 fps from my Colt 5 inch barrel. It takes less, only 4.2 grains, of Winchester Super Target to achieve the same velocity with this bullet. So, there should be less recoil with Super Target since it requires less of it (in weight) to produce the same velocity. And there was. I noted a slight reduction in recoil with Super Target. The difference in recoil when using these gunpowders was very small because the burning rate and charge weight are pretty similar, but there was a palpable difference. I've tested other gunpowders (and in other hangun calibers) and the burning rate priciple has been supported every time. There are likely exceptions to this rule of thumb (see box) but if you're trying to reduce recoil, using a faster burning gunpowder might do the trick.
A Caution About Pressure
While there are advantages to using faster burning gunpowders to reduce recoil, there are limits to the velocity that they can achieve before reaching maximum pressure compared to slower burning gunpowders.
Principle #1 above states: Faster burning gunpowders reach peak pressure more quickly than slower gunpowders. Consequently, a smaller charge weight is required for faster gunpowders to reach a given velocity.
Another way to view this is that fast gunpowders reach their maximum safe pressure with less gunpowder than slow gunpowders do. And, generally, the velocity achieved by fast gunpowders is less than the velocity achieved by slow gunpowders at the same pressure. So, slower gunpowders often (but not always) produce higher velocities than fast gunpowders when both are loaded to maximum pressure. Another way to look at it is that slow gunpowders can achieve the same velocity as fast gunpowders,
but at lower pressure.
http://38super.net/Pages/Recoil.htmlHow Recoil is Determined
Recoil is an expression of Newton’s third law of motion, which is often paraphrased as “for each action there is an equal and opposite reaction.” In other words, the bullet/shot and hot gases go forward, and the gun goes backwards. Various factors pertaining to the gun and bullet/shot determine not only the actual recoil energy that the shooter must absorb, but also subjective amount of recoil the shooter feels that they have experienced. I won’t get into the physics behind these facts for the sake of brevity, however this is basic high school physics. These factors which determine recoil are:
The mass of the gun - All things being equal, a heavier gun will have softer recoil.
The mass of the projectile - All things being equal, a lighter bullet/shot will have softer recoil.
The speed of the projectile - All other things being equal, a faster bullet will have heavier recoil, and the recoil will feel subjectively ’sharper’, since the recoil happens more quickly.