The 9mm G9 is a side-charging pistol-caliber carbine, or PCC. Whereas the G4 is chambered in 5.56, an intermediate rifle cartridge, the G9 is built around 9mm, a much more compact handgun cartridge.

Whereas you will trade off a little bit of firepower (and effective range) there is a considerable set of advantages to buying (or building) a PCC instead of an AR in a rifle caliber. Here are some of the biggest advantages.

A More Compact Footprint

The most obvious advantage of a pistol caliber carbine is that it is more compact than a full-size rifle, and depending on barrel length, can be more compact than rifle-caliber carbine, too.

This alone confers a lot of advantages to PCCs, not just to our specific platform; they are lighter, easier handling, easier to conceal, and overall better in close-quarters engagement. The smaller, more compact footprint also eases discretion during travel as well.

Easier Handling, Better Concealment

The smaller size and lighter weight of most pistol caliber carbines makes it easier to conceal them and on top of that, being lighter when shouldered, they are more nimble for close-quarter engagements. For this reason some prefer them for home defense guns, or for truck guns. Either way they excel for defensive applications.

Lower Recoil, Solid Stopping Power, Less Risk of Overpenetration

Assuming you buy or build a PCC chambered in 9mm, like a 9mm G9 side-charger, you will reap the benefit of substantially lower recoil when compared to 5.56, .223 or pretty much any other rifle caliber. This makes PCCs superior in terms of handling and recoil management, and makes them more accessible to smaller-framed shooters and the recoil-sensitive.

On top of that, you can shoot a PCC at the range all day with minimal fatigue; not that recoil is a problem with 5.56 or other small centerfire cartridges, but if you build an AR-style rifle around a heavier cartridge, it could be something to consider.

Also, when you build around an appropriate handgun cartridge, you’ll still get solid stopping power, even compared to some rifle cartridges. This brings up the idea of overpenetration.

While rifle cartridges produce better stopping power (and offer superior ranges) across the board, sometimes the extra performance is simply not merited. With that extra stopping power comes a much more pointed risk of overpenetration, which is always a risk that must be weighed with a defensive gun, especially one used in a home.

Naturally, the goal is to stop your target, but you want to do so without the bullet continuing through it. Rifle cartridges run this risk; handgun cartridges fire wider, slower bullets that are more effective at dumping their energy quickly and coming to a stop in the target rather than punching through. This actually gives some cartridges like 9mm, .40 S&W and .45 ACP an advantage over rifle cartridges, despite the fact that they are technically less powerful.

Ammo Availability

As an alternative to 5.56 or .223, 9mm doesn’t have that much advantage in terms of availability or accessibility. Most gun shops that sell one will sell the other. But once you get into other more niche rifle cartridges like 6mm ARC or .338 ARC, which almost no ammo manufacturers load anyway, it won’t be as easy for you to get ammo.

On top of that, niche cartridges are rarely if ever sold in bulk – but you can get bulk deals on common cartridges like 9mm, driving down the cost of your shooting habit.

Better Than a Handgun In Nearly Every Way

By this point, you might be thinking, “Alright, the 9mm has some advantages for defensive applications over 5.56 or other rifle cartridges – why shouldn’t I just use a handgun rather than a PCC?”

The answer is because a PCC is better in nearly every conceivable way than a handgun in the same chambering.

Yes, a handgun will be lighter and more compact, so strictly speaking, it will be better in close quarters. But it will underperform in every other way.

Handguns are harder to shoot accurately, they are harder to control, they produce more muzzle jump, they have lower capacity, they are not expandable, they have limited range and struggle at distances greater than 50 yards. On top of that, the shorter barrel of most handguns reduces ballistic performance.

PCCs have numerous attachment points, are more stable, are more accurate, and are more expandable, on top of a ton of other advantages.

The 9mm G9 Side-Charging Advantage

As with other side-charging AR builds, the 9mm G9 offers numerous additional advantages, including superior ergonomics, the ability to maintain a solid cheekweld while manipulating the action, and more room over the receiver for mounting optics.

For more information, see the previous link or get in touch with us directly.