TINCANBANDIT's Gunsmithing : September 2015

This post is a follow up to one I did regarding accessories for the Cx4 Storm back in January of 2014 (see it here).

That post has become very popular, so I decided to expand on it and tell you more about this great little carbine.
Honestly when I started this I had no idea how many reviews of this gun were out there.....oh well, maybe I can add something a little bit different?

Beretta's decision to design this gun was no doubt influenced by the lucrative LEO market, of which they have (or at least had) a good size chunk of. Offering a carbine that accepts the same magazines as the service pistol would be a bonus and may tip the scales in favor of Beretta.

The name "Storm" is an interesting choice. I immediately thought of the Nazi designed rifle from WWII: The Sturmgewehr 44. The name "Sturmgewehr" means "Storm Rifle" in German, the name was chosen personally by Hitler for "propaganda" reasons.
The Sturmgewehr 44, also known as the STG 44, is considered the World's first assault rifle. It was the inspiration for the AK-47 and I assume was also the inspiration for the name of this carbine from Beretta.
the Surmgewehr 44:

For those not following, the term "storm" is used in military and law enforcement circles for "attack" or "assault". For PC reasons Beretta could not have called this the "Cx4 Assault" or the "Cx4 Attack", better to use Storm and hope the PC police don't make a connection to the Nazi gun or the military use of the verb.

The "C" in Cx4 stands for Carbine, the companion pistol is known as the Px4, ("P" for Pistol)....The Military version of this carbine is known as the Mx4, it sports a 12" barrel and full automatic fire capability.

Pistol caliber carbines are nothing new, the benefit of having a more accurate carbine (with longer sight radius and perhaps an optic) chambered in the same cartridge as your side arm has long been favored by law enforcement (see my post regarding pistol caliber carbines here). It is even more advantageous when they can use the same magazine.

Currently Beretta offers two models, the Cx4 Storm Px4 model (in 9mm and .40 S&W) and the Cx4 Storm 90 model (in 9mm only).

The Cx4 Storm "Px4" model uses the magazines from the Px4 Pistol, while the "90" model uses the magazines from the 90 series pistols (model 92, 90-Two, M9, etc..).
In the past the carbine has been offered in other calibers such as 9x21mm, and 45 ACP.

The Cx4 Storm is a blow back operated gun, that means it uses no locking lugs like the Beretta Px4 or M92. This is a simple means of operating a gun, but it does have its drawbacks (which I will discuss later).

One unique feature (you lefties will love this) is the safety, magazine release, charging handle and ejection port are all reversible for left handed shooters.The bolt release, however, is fixed to the left side of the firearm.

The hammer forged barrel is 16.6" in length (12" on the Mx4) has a 6 groove right hand twist and is chrome lined. Here are the stats for the Cx4 Storm 90(click on the picture for a larger version), from Beretta

The front post sight is adjustable for both windage and elevation using the supplied adjustment tool. The rear flip sight has two apertures for snap shooting and long-range elevation selection. Both sights can be folded down when optics are mounted to the optional top rail. They can also be left in place to "co-witness" when using a red dot or holographic optic.

Speaking of tools, we should probably discuss what the gun comes with. My CX4 was an earlier one that came in a cardboard box (the box and gun suffered unmercifully from the previous owners dog...another story for another day). The cardboard was later changed to a hinged and padded plastic case.

The accouterments included: one forward mounted picatinny rail; a front sight tool; magazine loading tool; cleaning kit; spare magazine and owner's manual.

The included magazines with my gun were both the "California Compliant" 10 round versions, of course the 15, 18 and 32 round versions work equally well.

Factory magazines are made by Mec-Gar of Italy, these are of fine quality and are available labeled as Mec-Gar or Beretta in the aftermarket. Expect to pay $20-$30 each for the 15 rounders a few bucks more for the extended 18 rounders. The 32 round versions can be had for $35-$45.

Another option is to find some of the really affordable surplus military contract magazines. I have several Airtronic and Check-Mate surplus magazines that I paid a whopping $3 each for. To date I have had no issues with any of them.
Just as you can with many brands of 9mm magazines, aftermarket extended floor plates are available.

The designers of this gun intended for this gun to be carried by their owners and made sure the gun had the provisions to do so. On both sides of the butt stock can be found a sling attachment, there is also the typical sling swivel attachment fore and aft on the bottom of the stock (also note the spacer under the recoil pad....)

You may notice the front swivel attachment sticks out a bit, there is a reason for that. The front swivel mount acts as a button to release a hidden, telescoping pictanny rail.

photos courtesy of R. Doug Wicker

A picatinny tri-rail kit is available from the factory and the aftermarket, the ones I found were made of plastic. I cannot speak for the aftermarket ones, but the Beretta branded ones are quite sturdy.

Short carbines like this are designed to have a short length of pull, but if you need to adjust it, the gun comes with a spacer that can be removed or replaced with a larger one

Beretta sells the spacers on their website

Dis-assembly is relatively easy, you simply check to make sure the gun is empty, then check to make sure the gun is empty, then check again to make sure the gun is empty....Then push the take down pin out of its home mid stock. It is the tear-drop shaped button just forward of the trigger group.

The gun comes apart in three major pieces: The upper with the barrel/chamber & fore stock, The Lower: with the trigger/fire control group & butt stock. The third piece is the bolt carrier group.

Shooting the gun is a different experience. Prior to owning my Cx4 I had owned a Kel-Tec Sub 2000 and a Hi-Point 995 carbine, so I was not new to blow back 9mm carbines.

The large bolt feels strange as it reciprocates just below your cheek, something I did not notice as much with the Kel-Tec or Hi-Point.
The magazine release is impossible to manipulate in the shooting position (with it situated on the left side, moving it to the right might cause it to get pushed in inadvertently by my trigger finger). This is caused by the bar connecting the grip and butt stock, an inherent problem with thumb-hole style stocks.
The easy way to get around the problem is to roll your right hand and use your middle finger from below.
The safety is easily pushed to the "Fire" position with your trigger finger (moving it to the left), but getting it back to "Safe" (back to the right) requires the use of your left hand.
Other than these two issues, all the controls are easily accessed and manipulated.

My particular gun is picky on ammo, the heavy bolt will not function properly with the light plinking loads that I normally shoot in my Glock 19 (hand loads using 115gr copper plated bullets).
If standard velocity or factory loaded ammunition is used, the gun runs flawlessly.
When it comes to magazine issues, I have had none, partly because I stick to factory/Mec-Gar and contract surplus magazines and for the price you can get these for, why try to save a buck?

Accessories:
There are plenty of ways to accessorize the Cx4 Carbine.
One popular addition is covering the naked barrel with a flash suppressor, barrel shroud or dummy silencer.

You could also thread the barrel for 1/2" x 28 and use an AR style muzzle device. This is possible as the outside diameter of the barrel is approximately .69".

As discussed above picatinny rail kits are available to mount a myriad of accessories from lights and lasers to bi-pods and fore grips.
You can also add a spare mag carrier like this one from Desantis, called the Storm Packer

A few owners have removed the connector between the butt stock and the pistol grip

This guy did the opposite, to comply with the Unconstitutional laws in Commifornia

The guys from Sierra Papa Cx4 in Portland Oregon can modify your Cx4 to accept M4 style butt stocks. They also offer upgraded hammers, triggers and a host of other parts

Here is my Cx4 Carbine

See my post about how I accessorized my Cx4 here

I always like to end my posts with some examples of customized guns being discussed. I had no trouble finding plenty of these....