My Replica Pistol (CO2 .177 Air Pellet)
I wanted the authentic realism of a Beretta Pistol, the loading, handling and especially the blowback realism when firing the weapon. I enjoy the careful aim, the trigger pull and watching the bullet hit the cardboard target or tin can. It's pity there is not a loud explosive bang and smoke as the trigger is pulled but you cannot have it all? At least, I can fire the gun on my own land at targets within a minimum specified safe distance of the people and public walkways, which in my case is not a problem.

The two videos that sold me on the Umarex CO2 .177 Pellet Beretta PX-4 Storm Replica Pistol was this one that demonstrated an authentic firearm

AND - Andy's review video of the Umarex Beretta (CO2 .177 Pellet) PX-4 Storm loading and firing performance -

My Umarex Beretta PX-4 Storm -


I purchased the gun along with a spare magazine from Livelines Tackle and Guns in Scotland. The weapon cannot be shipped to a private home address. I had to produce my Scottish Air Weapon Certificate Licence at the shop. The Beretta is not a gun for carrying around in public. If I walk around in the UK with the gun in public view, especially with the pistol in a holster, I may find myself in the chokey, a guest of HM Prisons.

When you apply and receive your air weapon certificate licence it is very important that you adhere to any conditions for your use of the weapon. The main condition for my use states "The air weapon shall be used for the shooting of all lawful quarry, and for zeroing and practice on ranges and land, over which the holder has lawful authority to shoot". The Beretta PX-4 Storm air pistol has enough velocity and penetration power, especially at short range, to inflict a serious wound or even cause death to a person, so it is kept in a secure gun cabinet within my alarm protected home to deter theft and it falling into the wrong hands.

Umarex CO2 Gas Capsules & Crosman Pellgun Oil
I am a great believer in purchasing gun accessories (if possible) from the same manufacturer of the gun. So fortunately, Umarex supply their own CO2 gas capsules for their Beretta.

Purchasing the capsules in large numbers is probably the most cost effect way if you intend to regularly fire your Beretta and I have to admit, I enjoy firing my gun almost as much as riding my sports motorcycle.

My first purchase was 20 capsules but in the future, I will opt for 50 units which can be purchased from most on-line gun suppliers. Online you can use JS Ramsbottom to order and they ensure a swift delivery. Locally, I use Livelines Tackle and Guns in Scotland.

.177 - 8.3gr lead domed head with a 'ribbed' waist pellet, you can expect to achieve excellent velocity and accuracy with optimum penetration for up to 32 rounds from a Umarex CO2 Gas Capsule in a 1-10 yard range. With excellent accuracy but with reduced penetration you can go on and reach 48 rounds and even up to 60 but I recommend replacing the Umarex CO2 capsule at 48 rounds.

Before fitting a new Umarex CO2 Gas Capsule in the butt of my gun, I place a very small drop of Crosman Pellgun Oil on the tip of the CO2 capsule and then insert it up into the gun butt before I screw it home. The oil helps keep the air seals of the gun from drying out. NOTE: Do not put any more than a very small drop of oil on the CO2 capsule nozzle.

The Types of .177 Pellets
I have tried many different types of pellets in the Beretta PX-4 Storm, ranging from heavy lead to light alloy.  The ideal pellet proved to be the RWS SUPERDOME 8.3gr lead domed pellet with a 'ribbed' waist. Ideally suited for long distance accuracy for air rifles - it is equally at home in the Beretta PX-4 Storm within a 1-10 yard shooting range.

5.6gr Light Alloys: I have tried light alloy (non lead) pellets, including RWS Hypermax and RWS Hyperdome but these 'intermittently' jammed the magazine and proved very difficult in removing the crushed pellet between the magazine and the barrel entry point. You can access a jam by setting the gun to safety, removing the CO2 capsule and pull the (blowback) slide back to reveal the top of the magazine through the artificial ejector port.

Accuracy is greatly reduced if you fail to keep the rifled barrel of your gun clean and the working mechanism well oiled. The Umarex Beretta PX-4 Storm is just like any other weapon and must be maintained. I have included a Cleaning Section below on how to clean and oil the gun.

RWS SUPERDOME .177 pellets can be purchased online from
JS Ramsbottom.

Firing the Umarex Beretta PX-4 Storm Pistol
The Beretta is a beautiful piece of craftsmanship. When loading an Umarex CO2 capsule it is important to remember to open the butt base plate first (clockwise looking at the base of the butt) as this loosens the internal knurled black wheel and makes it free to turn. This knurled wheel's screw spindle is the often missed area for a few drops of Crosman's Pellgun Oil to keep it smoothly turning up against the base of the CO2 capsule, before finally closing the base plate (anti-clockwise looking at the base of the butt) to force up the capsule and break the CO2 seal.

Now having used the Beretta many times I have found one weakness in the CO2 capsule loading. Once or twice after inserting a capsule, I have fired the first shot and due to the vibration, the capsule has started to let out CO2 gas inside the butt. I have be fooled into thinking I have screwed up the black wheel tightly before finally closing the base plate to pierce the capsule nozzle inside the butt. There is very little margin for the base plate turning to finally pierce the capsule and I guess this is a deliberate design by Umarex to prevent overtightening the capsule nozzle against the silicone valve inside the gun. So, I have to screw the black wheel tight and even when I think it is tight, I still try and tighten it a bit more, before finally turning the baseplate.

The only other weakness that I have found with the gun is in the plastic magazine which holds 8 x pellets at each end and after 8 rounds are fired you eject it, turn it around and re-insert it for the next 8 rounds. It will invariable jam in the gun if you use alloy (non lead) 5.6gr pellets in a rapid fire situation. Another consideration to remember, is when you insert the magazine, there are 2 pellets visible and these must be tightly fitted into the plastic retainers because if they are in any way slightly proud of the retainers, they can catch and jam the magazine against the innards of the gun or worse, the breech, when the magazine is inserted. 

Having used a number of different lead and alloy pellets, the plastic magazine is a bit of a bummer because depending on how you retrieve it from the magazine holder or turn it around to re-insert in the gun, a pellet can fall out of it. This not a problem with
RWS SUPERDOME .177 8.3gr ribbed waist lead pellets, provided they are properly inserted in the magazine retainers. In any case, I now hold the gun pointing downwards and horizontal to the ground and eject the magazine. Then holding and turning the magazine with the loading side facing me and horizontal to the ground, I carefully insert the magazine back into the gun butt. Retrieving the magazine from the holster is a similar process of holding the magazine horizontally with the pellet loading side facing upwards.

I found there was no problem with the safety lever of the Beretta; sure it was tight to start with and required a finger from each hand to move it to fire but soon, I was able to pressure it back and flick it up to the fire position with the thumb of my left hand whilst holding the gun in my right hand. If the gun is cocked, you simply press the lever down with your left thumb and the gun hammer decocks without firing the pellet round.

The sights are fixed, so one has to make accuracy and velocity allowances for -

  • Umarex CO2 capsule power (dissipates at around 56 shots - using RWS Superdome 8.3gr .177 pellets - blowback fails at 60 shots)

  • Weight of the .177 pellets being fired

  • Range to the target

  • Any wind interference

With a brand new Umarex CO2 capsule inserted in the butt and using RWS SUPERDOME .177 8.3gr ribbed waist lead pellets, I fired off 32 rounds (2 magazines) at 10 yards at various tins cans. Many of the rounds penetrated right though both sides of the empty tin cans, whilst others penetrated only one side. The cans were the strong metal type (not a coke can).

As I continued to fire the Beretta, the power became progressively weaker and at around 48 rounds, the .177 pellets only dented the cans but accuracy was maintained. At around 56 rounds the power and accuracy were in trouble and at 60 rounds, the blowback slide of the gun failed and I could not hit the target.

Ideally, it would appear that for accuracy and velocity, a new CO2 capsule should be inserted in the gun at around 48 shots (2.5 magazines). When you remove an old CO2 capsule, you will hear the gas hiss as you unscrew it.

The gun is reasonably accurate when hand held and free of a support. If you shoot one handed, it is a very quick up to the gun site on the target and fire before the barrel weight creates a waver. Take into account, I am over 70 years old, so a younger guy might not have any problems with a single hand held shot.

The Beretta PX-4 Storm when hand held, even with both hands, is only likely (on average) to achieve a 2" diameter grouping of shots at 10 metres (10.94 yards, 32.9 feet) using
RWS SUPERDOME .177 8.3gr ribbed waist lead pellets. Place the Beretta on a support at 10 metres to the target and you will get the grouping down to a 1" diameter in the centre area. The guns sights are preset for a set distance which I think is approximately 10 metres - if you are any nearer to the target, the gun fires the pellet high when aimed at the centre. The Beretta proves its worth for rapid fire shooting at many different targets along with magazine changes - which is great fun.

Cleaning and Oiling the Beretta (480 Shots Fired)
I have designed a methodology for cleaning the gun. My main cleaning and lubrication tools are Walther Oil Filled CO2 Maintenance Capsules along with
Crosman Pellgun Oil  and VFG Discofelt .177 Cleaning Pellets.

Gun  Accuracy After Cleaning
I have found that once my gun barrel is cleaned, I have to fire about 20 x RWS Superdome 8.3gr lead pellets before the gun's accuracy is fully restored.

Lubricating the Inner Seals
The main CO2 capsule seal of the gun is lubricated every time I fit a new Umarex CO2 capsule but there are other seals inside the mechanism that require to be addressed. To do this I use a Walther 'Oil Filled' CO2 Maintenance Capsule as recommended by Umarex. I remove the magazine, fit the Walther capsule in the butt and fire the gun until the CO2 and oil are exhausted. I then clean off any excess oil of the exterior body of the gun.

Oiled magazine mechanisms, especially oil on the rotation loading mechanism can jump or jam pellets. Walther advise that if you are using a Walther OIL Maintenance CO2 Gas Capsule, you remove the magazine first. Once you have cleaned and oiled your air weapon and then when inserting a magazine, especially a plastic one, remove it again and make sure that any trace of oil from the internals of the gun are wiped down, especially the rotating section of the magazine where the pellets are housed. You may have to do this a few times to dispel any excess oil.

I had a hard time finding the Walther OIL Cleaning Capsules but eventually I traced them to Solware which is an online supplier and the delivery (1 day) was spot on.

Cleaning the Barrel
I then clean the barrel by
loading a magazine - one end with 8 x VFG slightly Pellgun oiled pellets and the other end with 8 x VFG dry pellets. I fire the oiled pellets first, followed by the dry pellets into a collection bin and then inspect the fibre pellets for signs of cleaning.

VFG .177 Fibre Cleaning Pellets are ideal for using to clean the barrel of the Beretta PX-4 Storm pistol. They fit the magazine loading bays perfectly and are fired through the barrel with ease.

Pellgun Oil is also ideal for lubricating moving mechanical parts that can be accessed without stripping the gun.

I was able to trace VFG Fibre Cleaning Pellets at JS Ramsbottom

Cleaning and Oiling the Gun Mechanicals
The Beretta has a metal top section on a composite body. It has several metal moving parts that require a few drops of Crosman's Pellgun Oil - I remove the magazine and the CO2 capsule to gain access to these areas -

  • The black wheel spindle in base of butt (used for tightening up the CO2 capsule) - see Note below

  • Trigger hole (gun held upside down)

  • Safety catch (gun held on it's left side)

  • Hammer section (all moving parts)

  • Blowback slide (a few light oil drops where slide meets the body - both sides of gun)

Note: When turning the black wheel to oil and disperse oil on the screw spindle - first, make sure you have opened the base plate on the bottom of the butt before you attempt to turn the wheel.

After oiling, move all the parts several times to disperse the oil evenly. Do not fire the gun (CO2 capsule and magazine still removed) flick the safety switch to red dot/fire, pull the blowback slide right back to cock the hammer and flick the safety switch to safe and the hammer decocks. Repeat but this time, hold the hammer, pull the trigger and slowly release hammer head back to the strike plate in the body - repeat and alternate these processes several times.
Finally, clean any excess oil from the gun's body with a dry absorbent cloth.

Gun Storage
For long-term storing of the gun, I  will clean and oil it as above and store it with a drip of Crosman Pellgun Oil on its CO2 entrance nozzle in the butt, no Umarex CO2 gas capsule fitted and the 2 x magazines are left empty and out of the gun.

Stripping Down the Beretta PX-4 Storm
The Beretta's internals, especially the blowback slide will eventually require cleaning and oiling. Over time and dependent on it's use, the gun will become filled with crud made up of dust and grime mixed with lubricant. The Beretta PX-4 Storm can be field stripped BUT be warned, it will invalidate the manufacturer's warranty.

However, to field strip the gun, you will have to remove the very small solid steel pin which sits in the concave section of the gun's body ahead of the trigger guard of the gun and forward of the larger split pin in the concave section. You do this by knocking it out from the left side of the gun using a 'Starlett Pin Punch' of a similar size with a light blow administered - the pin is actually quite loose and only held by a hex engraving on the right side. The pin will come out on the right of the gun and you will see the other end of the pin has the hex engraving which bites into the right side composite of the gun body to hold the pin in place.

You then push the blowback slide right to the back and gently lift it's rear upwards and forwards to remove. Carefully remove the spring from the barrel by pushing it along the barrel from the back - do not pull it. Clean and re-oil the gun body mechanicals, blowback slide sections and main spring, then gently refit the spring on the barrel (smaller end first) without harsh pushing or pulling. Make sure that the small block under the base of the barrel has it's 2 springs still in place. Slide the blowback slide on from the front and all the way back, raising the back slightly and drop over (allow it to come forward) to secure.

Now, gently lift the tab which has appeared in front of the trigger (this raises the 2 spring block inside the gun) and slide in the pin (from the right side of the gun) with your fingers holding the hex end, most of the pin will easily slide back in until the hex part meets the gun's body. Now gently tap in the pin from the right side of the gun using the 'Starlett Pin Punch'  until the hex part bites and both sides are flush with the concave sections of the gun. If for whatever reason over the years (after strip downs, cleaning and re-oiling) the pin has become slack at the hex end, place a small drop of matt black paint on each end to bond it to the composite material of the concaves to prevent it slipping out.

I have put in links to the suppliers of these targets - please click on an image to open up the link. My Umarex Beretta PX-4 Storm is fairly accurate but it might prove a bit of a stretch in me hitting the dead centre of those Remington 'Knock Down' figures or similar targets - perhaps 3 in 8 shots?

I have started collecting tin cans from the dog food that I feed to my foxes which make for great targets standing on a fence. I also like the metal container (pellet collector) that holds paper targets. It can be easily fixed or hung on a nail to a fence post.

A neat solution is the metal gong, which resonates when a bullet hits it and could prove ideal - it comes in all sizes -

Another ideal target might be the exploding Splatterburst figure?

My Holster for the Beretta PX-4 Storm
I found the ideal holster in the Umarex Belt Holster which is made of ballistic nylon with a section for a spare magazine and the gun is held in place by a clip over strap.

The holster is slid over your trouser belt and has 'Velcro Heavy Duty Fixings' on the back with an additional cross lock Velcro strap to firmly secure it -


Video of my Gun & Holster
Work in Progress
- I will have a video of my use of the Beretta - up and running very soon.


If you have enjoyed this article - please donate to my charity of choice  -  The Sick Kids

Richard Lawrence
United Kingdom