View Full Version : Cx4 Storm

03-13-2004, 07:27 AM
A major LE agency asked me to look over this carbine and comment on same. It was a 9mm with an LE magazine and no manual.

Beretta Cx4 Storm

This 9mm Para carbine is about 30 inches overall length, about 7 inches at its tallest measurement. Line of sight is about 2 inches above the line of the bore, so any added optic will be at least that high. The rear sight apertures were sized at SMALL and SMALL. One of the apertures need to be opened up to allow this carbine to be used to its full potential, if that be any sort of self defense.
The aperture settings are marked as LR and SR.

This carbine is outfitted with an optional rail on top, between the sights, allowing for a possible combination of sight and NV device. Added to the forearm is a polymer based assembly that creates three accessory mounting points via rails. Sight rail and forearm accessory are optional items. Pressing the front sling swivel stud allows another accessory base to extend from the front of the forearm, creating the most useful point for locating accessories, immediately under the barrel. Overall design comes from the Italian design group currently responsible for several of Beretta's products. Weight is centrally located and gives the carbine a lively feel. The design would allow for some means of shortening or reducing the stock length, but not in today's political climate.

The bolt design owes lineage to Beretta's fine PM12 sub-machine gun. The bolt telescopes around the rear of the barrel. Lock up is very simple in that the carbine fires from an unlocked closed bolt, in essence, a blow back operation. In some less robust designs, this has led to functioning problems with high pressure ammunition. I suspect this will not be an issue with the Beretta product, but one that should be tested before one employs such ammunition. The bolt contains what appears to be a free floating firing pin that is restrained by a firing pin safety, essential for a blow back gun of this sort. An examination of the bolt reveals potential for minimal design change to accommodate additional modes of fire. Driving the firing pin forward is a polymer hammer which uses the latest structural additions to make such polymer parts resistant to shatter caused by wear and impact on steel. The operating handle is attached to the bolt and readily removable. This handle is one of a series of parts that can be moved to change ejection to either left or right. The handle snaps into the bolt body and normally retained in place by the design of the receiver. The operating handle reciprocates with the bolt, which is often disqualifying under some units Mission Essential Needs Statement. The barrel crown uses a simple bevel that protects the rifling, but caused quite a bit of build up on the bevel from burnt powder.

A quick function check seemed to indicate that the carbine was ready to shoot. Loading it up with a variety of cartridges from the loose rounds box, I went to the 25 yard line. I quickly discovered that the carbine had been assembled for a left hand ejection, though the ejection port cover remained on the left side. This combination, easily produced, created a single shot carbine that attempted to eject to the left and created stoppages that were not easily cleared. I returned to the range house determined to either get it to work or lose some parts in the process. Within ten minutes I located the problem and had the parts changed to allowing normal functioning. After that the carbine worked fine, feeding and firing any of the junk rounds I could find to run through it. My largest mechanical concern would be the ease with which one can create a non-functional firearm.

The included magazine is of Beretta mfg. and seems better built then many of the aftermarket magazines made for the military. It loaded 15 rounds easily. The magazine base plate is quite robust and appears to be a polymer formulation and design that I have not seen before. I suspect it will take quite a bit of dropping onto concrete without ill effect.

The largest question in my mind was that of the role for this gun. Pistol caliber carbines have not generated a large following. For the same envelope size, one could obtain a .223 caliber gun that would do everything the Storm will do, and then some. If this gun were outfitted with a ten inch barrel, high efficiency suppressor, the existing extended capacity magazines from the Beretta 93R and a select fire mode, we'd have a contender for the sub gun market.

The butt stock has sling attachment points on each side, but no complimentary attachment points on the forearm. Two sling swivel studs are provided.

The magazine release is located on the left side of the pistol grip, similar to most handgun magazine locations. The release button protrudes above the surrounding surface and is easily used, or bumped, and readily releases the magazine. It could use better design to protect the button.

The bolt release lever is located in a position that is best described as similar to the safety on a 1911A1 type handgun. It readily released the bolt, even when actuated by an empty magazine. Oddly, it is not ambidextrous and not readily used by a left handed shooter.

The trigger blocking safety, a cross bolt type marked with red for “fire”, is located above trigger and easily used by the right hand trigger finger. I was not able to figure out if this part can be changed to left hand operation. This safety, when in the fire position, has the potential for being bumped easily into “safe” position and creating an inert firearm. This is notable as many designs for LE/Military avoid operating levers or buttons that might be inadvertently activated by allowing the weapon to fall to a slung position. With the weapon being allowed to fall or rest into a slung position, operator equipment or load bearing gear may cause the safety or magazine release to be activated, either being undesirable for a serious use firearm.

This weapon would be useful for personal defense and with a few design changes, some law enforcement applications. As it is, it is not comparable in function or utility to any other design of handgun, carbine or shotgun, if such is essential to an entities comprehensive training agenda. The caliber is a major limitation, as when a pistol bullet gets to 100 yards, it is a pretty tired bullet and the velocity is reduced to below the design limits of most major projectile designs. Finally, I would be suspect of its long term durability as compared to the MP5 or AR type firearms.

Thanks for the opportunity to examine this firearm in detail.

03-14-2004, 12:33 PM
Kilroy thanks for the write up, I'm still up in the air as far as pistol carbines go for issue, although I still have and carry a Marlin in 45acp some times, sounds like it would make a decent issue for the street troopies tho

03-14-2004, 05:44 PM
After a few rough and tumble exercises, I found that some impacts on the left side of the gun will eject the magazine and put the cross bolt safety into "safe" position. Rather unhandy when I need to fire.