Regular readers (hello to you both!) may have noticed that I have already posted a review of the Umarex PX4 Strom back in 2014. That was based on my ownership of two PX4s between 2010 and 2013. So, you might be wondering what more I have to say about this particular replica? Well, here’s the thing; I rather like the PX4 but for me, it was marred by one particular issue – namely an inability to shoot to the point of aim. Both my PX4s shot sufficiently high and to the left at 6m that I didn’t bother with them much.
Which was a pity because there’s actually a lot to like about this air pistol. It’s a licensed blowback replica with full markings and, being a pellet shooter with a rifled barrel, it should be an accurate shooter. I have read on other sites that, somewhere around 2014/2015 the design of the PX4 was changed and that it’s now better. I have also read elsewhere that the accuracy issues on this replica are caused by the plastic outer-barrel shroud interfering with the flight of the pellet as it leaves the end of the barrel, and that over time this decreases as the plastic is worn away.
I intend to re-visit the PX4 to find out whether either of these things are true and, if they are not, to look at how I can otherwise improve how it shoots. So this review will be a little different as it will include comparison between the PX4 I have now and my earlier experience as well as information on how it can be improved as a shooter. Will I end up with an accurate shooter or yet another PX4 that gathers dust in the back of the gun cupboard? Let’s find out…
Real Steel Background
Beretta launched the PX4 Storm in 2004 as a replacement for the 8000 (Cougar) series of pistols, a more compact alternative to the Beretta 92. The PX4 is a polymer framed semi-automatic pistol that uses the rotating barrel locking system from the 8000 series and the trigger and safety system from the Beretta 92.
This was Beretta’s second polymer-framed handgun and it borrows many of the design cues from the first, the Beretta 9000 which was designed by the Giorgietto Giugiaro Design group. The PX4 is still in production and has proved popular as a law enforcement weapon in the US, Canada, Italy and Argentina amongst many others.
Unlike most other Beretta pistols, the PX4 has a fully enclosed slide. It is available as several models both with and without a manual safety and chambered for 9mm, .40 S&W and .45 ACP. Its distinctive looks have led to the PX4 featuring in a number of television shows and several movies Inception (2010), The A-Team (2010), Taken 2 (2012), Robocop (2014), and John Wick Chapter 2 (2017).
Leonardo DiCaprio with PX4 in Inception (2010)
The Umarex Beretta PX4
The Umarex Beretta PX4 was launched in 2008 and was at that time only the second pellet-shooting blowback replica from that company – the first, the Magnum Research Desert Eagle appeared in 2005. This a CO2-powered blowback replica with a polymer frame and a metal slide. It has a four-inch rifled barrel and can shoot both .177 pellets and 4.5mm steel BBs stored in a double-ended magazine that hold up to eight BBs or pellets in each end. This is a fully licensed replica that features Beretta markings.
It is manufactured in Japan on behalf of Umarex, though I don’t know who actually makes it. I have seen a number of claims that this replica was updated and (perhaps?) improved around 2014. I have not been able to confirm this and most claims are a little vague about precisely what changes have been made to the original model. Part of the reason for this review is to find out whether this really is a new model and whether it’s any better than the original.
Calibre: 4.5mm BBs/.177″ pellets
Magazine capacity: Sixteen .177″ pellets or 4.5mm steel BBs
Barrel length: 4″, rifled
Weight: 720g (1.59 pounds)
Overall length: 7½”
Sights: Fixed front and rear with white dots
Packaging and presentation (3/5)
My Umarex PX4 came in a sturdy card box that contains the pistol, a single magazine and a multi-language user manual. The box did seem a little better than most, being strong and provided with things like a small square of foam to stop the manual safety from rubbing against the box lid.
This is not the same box that either of my previous PX4s came in. So, at the very least, I can say confidently that the box has changed…
Visual accuracy 7/10
Externally, this PX4 seems identical to both my earlier models. It’s a pretty fair representation of the original including overall size and shape and full Beretta markings.
The only visual anomalies are the manual safety on the right of the frame, the base of the grip and safety markings on the right of the slide and frame, though at least these aren’t highlighted in white. The slide-mounted manual safety and slide release catch are moulded in place and have no function, but at least they look pretty good and don’t detract from the overall appearance.
Functional Accuracy 6/15
Functionally, this is identical to my earlier PX4s. The trigger, hammer and magazine work as per the original but the slide doesn’t move through a full range, it doesn’t lock back on empty and the slide release doesn’t work. You can lock the slide back, simply by pulling the trigger while the slide is held to the rear, but this really serves no purpose. The manual safety does feature a decocker – when you move it to the “S” position, it safely drops the hammer, and that’s quite useful if you are leaving this replica with CO2 in it (though you shouldn’t do that for extended periods or it can degrade the CO2 seal). To move the manual safety from “S” to “F,” you have to pull back on the serrated centre section, a fingernail-breaking job. Happily, to move it in the opposite direction, you don’t need to do this.
OK, so for me, this is the most important part of this review – does this PX4 shoot any better than the previous examples I owned? The first thing I looked at was the plastic outer barrel shroud – I have seen claims that this can interfere with the flight of the pellet or BB as it leaves the inner rifled barrel. It’s certainly notable that this plastic outer barrel is very close to the inner barrel and, if you look closely, it isn’t perfectly circular – there are irregularities that look like mould marks that project inwards. If you look at the image below, you’ll see one at around the two o’clock position.
Is it possible that these deflect the pellet as it leaves the rifled barrel? We’ll have to wait and see. Getting the Umarex PX4 ready to shoot is straightforward. The lower rear part of the grip is removed to reveal the CO2 chamber.
The bottom of the grip is twisted clockwise, the CO2 cartridge is inserted and then the knurled wheel is finger tightened. Then, the base of the grip is turned counter-clockwise and this pierces the CO2. I get full four magazines to a single CO2 – that’s over 60 shots, which isn’t too bad for a blowback replica though the last couple of shots do sound as if they’re a little down on power.
Back in 2008 when this replica was first released, the magazine was pretty novel, though similar designs have since been used in a number of other replicas. It’s double-ended and at each end there are eight chambers into each of which you can load a pellet or BB.
Only two chambers are visible at a time and you then have to click the magazine round to expose the next two. It’s a little fiddly and time-consuming but fairly easy. Pellets are a friction fit and steel BBs are retained by a magnet. With this replica loaded it’s time to shoot, and the first thing I want to talk about is the trigger. It works in both double and single action and the double action pull is predictably long and heavy. However, even in single action it’s a long pull and the first 70% or so does nothing – there is barely any resistance until you come to the point where the next pellet is indexed in the rotary magazine. This isn’t especially heavy, but it happens just before the release point. My technique with this pistol is to pull the trigger past the indexing point and to pause just before the release before the final pull. But, more than once, I found myself unintentionally shooting as I pulled the trigger past the indexing point and through the release point. This isn’t a nasty trigger, it’s just different and, if you use it as I do, it’s worth being fairly careful.
Finally, it’s time to shoot. And it soon becomes apparent that this new PX4 isn’t as bad in terms of accuracy as my previous versions – it’s much worse! The image below shows the result of sixteen shots at 6m range using Umarex 0.48g Mosquito flat-fronted pellets. The aim point was the base of the centre black circle.
This was taken after more than 150 shots, to give the barrel a chance to lead-in. As you can see, the shots are scattered mainly to the right of the target and not all sixteen have even hit my 14cm square target. I tried a couple of other types of target pellet and all gave similar results. This is very disappointing – shooting pellets through a rifled barrel should give much tighter groups than this. Most of my airsoft and BB shooting replicas can do better than this! Both my previous PX4s were capable of 1 – 1½” groups at 6m, though they were high and to left of the aim point. But, this is also puzzling. You can actually see the pellets deflecting to the right as they leave the barrel. What’s going on here and, most importantly, can it be fixed?
Intermission – Improving the PX4
OK, so it’s time to find out what the problem is. I have read in other sites a suggestion that inaccuracy is caused by the front face of the outer plastic barrel interfering with the flight of the pellet. And, if you look closely, you can see that the inner and outer barrels aren’t quite concentric and that the lower part of the plastic barrel does seem to overlap with the bore of the inner metal barrel. I’m going to describe what I did to improve my PX4, but please do remember that if you do these things, you will void your warranty and you may even end up with a replica that won’t shoot properly or at all. So, don’t do any of this unless you are confident in your ability. You have been warned!
To test whether this is causing the problem, I want to enlarge the hole in the outer barrel. To avoid the possibility of damaging the rifled barrel, I’ll disassemble first and fortunately, this isn’t difficult (you’ll find a link to a disassembly guide at the end of this review). To remove the slide and remove the firing valve only requires the removal of three pins and once the valve is out, you can remove the inner barrel and the plastic breech block.
Then, I widened the opening in the outer barrel and this is the result. Yes, I know, it’s pretty rough – I’ll clean it up later but all I want to do for the moment is see if this makes a difference to shooting. You actually have to be pretty careful when you’re doing this. The end of the plastic barrel is the only thing that retains the inner barrel in place – if you remove too much material, you could make this replica inoperable.
I put it all back together, load up with the same pellets, and here’s the result of sixteen shots at 6m.
That’s quite a dramatic improvement. The vertical spread was previously over six inches. Now, it’s down to around 1½”. So, the the pellets were hitting the plastic outer barrel and that was making a difference to accuracy. Now, I want to look at whether I can move the centre of the group to the left to coincide more closely with the point of aim and to tighten it up further.
I disassemble again and this time, I’m looking at the fit of the rifled barrel into the plastic breech block. It’s notable that the fit is quite loose – the metal barrel pushes into the breech block and I note that it can move around quite a lot and the fit in the plastic block is all that gives it support.
I go for the simplest solution – a small strip of adhesive tape round the base of the barrel makes it a tight push-fit into the breech block and it no longer has any play. I reassemble and try shooting again. Here’s the result, with the aim point still at the base of the inner black circle.
That’s more like it! The group is still a little to the right, but it’s now close to spot-on for elevation and the overall group is just over 1”.
Shooting – Part 2
Now that I have the PX4 shooting reasonably, I enjoy it much more. This is actually a very nice replica to shoot. It has good weight, the blowback is strong and the pellets hit the target with a great deal of power (my chrony shows around 350 – 360fps). And now, by aiming off a little to the left, I can get reasonable groups close to the centre of the target. Here’s the result of a full magazine, fired fairly rapidly from 6m.
These few simple mods to the PX4 have transformed it as a shooter. Out of the box, it was so inaccurate that shooting was basically a waste of time. Now, I can appreciate the good things about this replica and actually enjoy shooting it. I like the fact that it isn’t too loud, I appreciate the fact that I can get 60 shots per CO2 and I especially like that this replicates the feel of shooting the real steel more closely than many replicas. The score for this section is for this pistol after I had done these few mods. As it was out of the box, it would have scored much lower.
Quality and reliability 11/15
One of the things I didn’t like about both my pre-2014 PX4s was that the slide didn’t fit well and rattled annoyingly from side to side. That problem has vanished now – on this version the slide fits very well indeed and the movement of the slide feels more precise and better engineered. Overall, this feels like a good quality replica and I haven’t experienced any functional problems with loading CO2, pellets or with shooting.
The problem with the plastic outer barrel fouling the pellets as they leave the barrel is pretty poor and any sort of reasonable quality control should have picked this up long ago. It isn’t difficult to fix, but really, you shouldn’t have to think about fixing a new replica. Likewise the loose fit of the rifled metal barrel in the plastic breech block – this means that you are never going to get tight groups and it just shouldn’t have left the factory like this. Like the problem with the outer barrel, it’s easily fixed, but it should need this done just to get it to shoot straight.
So, I’m conflicted as to what to say here about quality. This does seem like a good quality replica in many ways, but what I got was the basis for something to work on rather than a pistol that shoots well out of the box. Now, it’s possible that I was unlucky and that I got a poorly finished and assembled PX4, but looking at other reviews online, I’m not the only one to experience a lack of accuracy with this replica. If you are lucky enough to get a good one, this is a great replica. If you get one like mine, you’ll have to be prepared to do a little work to turn it into an acceptable target shooter.
Overall Impression 8/10
This looks and feels like a well made and finished replica. It’s solid, the action of the slide now feels very good and the trigger, though it takes some getting used to, actually isn’t too bad. I guess the best thing I can say about it is that, now that the problems are fixed, I really enjoy shooting it.
Overall, this does feel a little different to the two previous versions of this replica that I owned before 2014. The fit of the slide and its action are now much better and overall it looks and feels good. However, as a shooter, it was simply dire out of the box. With a little work I have managed to change that and I now do really enjoy shooting the PX4.
Whether you choose to buy one of these probably depends on whether you feel confident to disassemble and make some small changes. You might be lucky and get one that doesn’t need these things done, but if you get one like mine, you will probably not be prepared to put up with its atrocious accuracy out of the box. So, if you’re willing to put in a little time and effort, this can be made into a very decent replica for not a great deal of cash.
Total Score (after modification) – 73/100
Here’s a link to a step-by-step disassembly guide for the PX4. Remember, to do the mods described here, you only need to remove the slide and the firing valve – that means you only have to remove three pins.