Inherently Subsonic Ammunition

Inherently Subsonic Ammunition

Hey all, we here at True Shot Academy are going to go over inherently subsonic ammunition today. Essentially, we are going to be covering specific calibers and loadings which are subsonic in nature despite not often being marked as such. Additionally, we are going to delve into some considerations regarding subsonic ammunition, firearms, and more. Without further ado, let’s talk about inherently subsonic ammunition.

What is Subsonic Ammunition?

Put simply, subsonic ammunition is ammo which propels projectiles at subsonic velocities. This is to say that these loadings will not break the sound barrier as they are not supersonic. Subsonic velocities are dependent on the powder charge of a given loading and the weight and type of projectiles utilized. These velocities are either inherent to a specific caliber or loading or are purposefully achieved with specialized subsonic loadings. Put plainly, some ammo is simply subsonic by nature while other loadings are designed to be subsonic. Subsonic ammunition is well-suited for use with suppressors due to low velocities and noise produced by loadings of this type. If one is after a hearing safe suppressor loading, one will be well-served by subsonic ammunition.

Do You Still Need Ear Protection?

One should still utilize proper ear protection when employing subsonic loadings. Even though loadings are not traveling at supersonic velocities and do not feature reports with the telltale supersonic “crack,” some form of ear protection is still essential. Instant, permanent hearing damage can still occur if hearing protection is not utilized. Of course, the addition of a suppressor when paired with the right loading can produce hearing safe levels of noise. Ear protection is still worth considering when suppressors are used. Suppressors do not always guarantee a hearing safe noise level, especially if non-subsonic ammo is used. Additionally, other shooters may not be using suppressors and optimal ammunition, meaning that ear protection is still necessary. All in all, it is better to be safe than sorry as ear protection is easy to use and can protect you from permanent hearing loss. Purchase Ammo

Why Does Velocity Matter?

Velocity is important as it directly relates to a loading’s status as either supersonic or subsonic. Put plainly, supersonic loadings feature high velocities while subsonic loadings feature low velocities. The threshold for supersonic ammunition is about 1,100 FPS. This is to say that anything below this value is subsonic while everything above this value is supersonic. As the name suggests, subsonic loadings are quieter than their supersonic counterparts which break the sound barrier. The charge of a given loading is a prominent influence on potential velocities. High-pressure calibers and loadings are conducive to high velocities while light loadings generally produce low velocities. Of course, other factors such as environmental conditions, altitude, and barrel length can influence the actual velocity observed by a shooter.

Barrel Length Is Important

As mentioned above, a firearm’s barrel length is important when dealing with velocities and potentially subsonic ammunition. Longer barrels are conducive to higher velocities while shorter barrels generally facilitate lower velocities. Simply put, one should know longer barrels tend to accelerate projectiles and can potentially place some loadings into the supersonic range. Shorter barrels provide less time for projectiles to be propelled and accelerate, often yielding low and subsonic velocities. Some ammunition manufacturers state which firearms or barrel lengths were used for velocity testing while others do not. One should keep this in mind if looking for a specific velocity and weigh this value against what they are intending to shoot. Rifles will produce higher velocities than pistols will. This is to say that one can expect to achieve lower velocities with a handgun than they will with a rifle. At the end of the day, one should be ready for the reality that their actual, achievable velocity may not exactly match what is on their ammo box.

.22 Long Rifle

The .22 Long Rifle cartridge is one of the most common calibers on the market. This rimfire caliber is employed by shooters of all types and for many purposes. Shooters will typically encounter 40 grain lead round nose (LRN) or copper plated .22 LR loadings in standard velocity form. Generally speaking, standard velocity .22 LR ammo clocks in at about 1,050 – 1,070 FPS, placing it right below the supersonic threshold. Standard velocity loadings are especially well-suited to suppression in handgun barrels as velocities are low and will not reach the supersonic range. This is why Ruger Mk IV pistols are some of the most popular suppressor hosts in America. Additionally, some standard velocity loadings can remain subsonic even in rifles as a full powder burn is achieved well before the projectile clears the muzzle.

.38 Special

While most shooters typically associate the cartridge with snub nose revolvers, the .38 Special is also commonly employed in rifles. Specifically, many shooters have utilized .38 Special ammo in lever action rifles in .357 Magnum as it is cheaper to shoot and plentiful. Most readily available factory .38 Special ammunition with full metal jacket (FMJ), LRN, and wadcutter projectiles yield subsonic velocities. Of course, +P loadings and specialty defensive loadings will potentially cross into supersonic territory when fired from a rifle. These loadings tend to exist in the 130 to 158 grain range and tend to produce velocities under 1,100 FPS when fired from a rifle. This fact makes .38 Special ammunition, especially heavier 158 grain offerings, a joy to shoot with a suppressed levergun.

9mm Luger

The 9mm Luger, often just called 9mm, is one of the most common and popular handgun cartridges in circulation. Shooters employ 9mm ammo in handguns, subguns, and pistol caliber carbines (PCCs) for various purposes. As far as subsonic 9mm ammo goes, loadings of this type will generally be found in the 147 to 160 grain range. 147 grain offerings are most common and come in many diverse options. Shooters can encounter purpose-built subsonic ammo and inherently subsonic 147 grain 9mm ammo. In terms of inherently subsonic 9mm 147 grain ammo, there are many standard loadings which produce velocities under 1,100 FPS. Of course, barrel length is a factor, and some loadings may exceed subsonic velocities with longer barrels. Additionally, there are some 147 grain loadings which produce supersonic velocities. Shooters can take advantage of specialized and inherent subsonic 9mm ammunition for fun suppressed shooting.

.45 ACP

The .45 ACP is another one of the most popular handgun calibers one will find on the market. Pistols have been chambered in this cartridge since its introduction over a century ago. While shooters today tend to prefer 9mm, the .45 ACP still sees widespread use among suppressed shooters and PCC shooters. The cartridge is well-suited to suppression due to its low velocities and heavy projectiles. Shooters will find that 230 grain factory ball ammo is inherently subsonic and readily available. This makes it easy for suppressed shooters to pick up .45 ACP ammo which is optimal for suppressed shooting.

.300 Blackout

The .300 Blackout is another caliber which is often suppressed and employed by shooters of all types. Tactical shooters and hunters alike enjoy the cartridge and its benefits, especially when appropriate loadings are paired with suppressors. Loadings for .300 Blackout are often found in either supersonic form or subsonic form. As with most popular calibers, there are many clearly labeled .300 Blackout ammo offerings which make their subsonic status evident. Some shooters think that any loading not marked as “subsonic” are supersonic, an assumption which is not always true. In fact, there are many 220 grain .300 Blackout loadings which will be in the subsonic velocity range and are not marked as such. Simply put, .300 Blackout ammunition with 220 grain projectiles and heavier should be subsonic, whether marked as such or not. Purchase Ammo

Not An Exhaustive List

Of course, this is not an exhaustive list of inherently subsonic calibers or loadings. There are many other calibers, specifically smaller handgun calibers, which are also inherently subsonic in nature which were not explored in this article. This is simply because these calibers are not as widely used by shooters in general or among suppressor users. The aforementioned calibers are easily accessible and are in common use with shooters of all types, particularly those with suppressors. The existence of inherently subsonic loadings for these calibers as is also not widely known.

Is Subsonic Marked Ammo Worth It?

The short answer is ultimately “yes” as there are many things to consider. While inherently subsonic loadings for these calibers and others do exist, one should not completely write off subsonic marked ammo. Subsonic marked ammo is specifically optimized for suppression. This is to say that these loadings are tuned for suppression in more ways than simply achieving subsonic velocities. These loadings can feature specialized projectiles, propellants, and components which further optimize their performance and the shooter’s experience. Often, manufacturers invest a great deal of R&D in creating loadings which are conducive to good suppression and reliable function in a wide variety of firearms. In short, while these inherently subsonic loadings exist, dedicated subsonic loadings still have their place.

Conclusion

All in all, it pays to know which loadings and rounds can potentially be inherently subsonic. Doing so can allow for optimal suppressed shooting and enjoyable experiences at the range. We here at True Shot Ammo carry loadings for every caliber mentioned on this list in our large inventory of ammo for sale. Additionally, our inventory of ammunition for sale covers popular calibers and gauges like 9mm, 5.56, 12 gauge, and .22 LR. Whether you want loadings for one of the aforementioned calibers or want to buy bulk ammo, we have you covered. As always, happy shooting.