Gamo GX-40: do accuracy and handling really come at a cost?

The British-made Gamo GX-40 is a multi-shot bolt-action PCP that’s been clad in a black tactical-looking synthetic thumbhole stock and comes with one 10-shot magazine and a muzzle brake. (Read our list of PCP air rifles under £500.) 

Some sacrifices have been made, as the polymer stock has no degree of adjustability – but, despite the no-frills nature of this gun it’s in no way lacking with regard to performance. (Read our list of the best air rifles under £500.) 

Key Specs for the Gamo GX-40

Gun supplied by: Gamo  Model: GX-40 Price: £379 Type: PCP Calibre: .177 (on test) and .22 Action: Bolt-action Magazine: Multi-shot (10 shots for both .177 and .22) Overall length: 96cm (37.8”) including muzzle brake Barrel length: 47cm (18.5”) Weight: 3.0kg Stock: Ambidextrous synthetic thumbhole Sights: Dovetail rail Length of pull: 37cm (14.6”) Trigger: Two-stage, adjustable Trigger-pull: 1lb 12oz Safety: Manual, resettable Muzzle energy: 10.3 ft-lb

Stock

The GX-40 reminds me of another Gamo model that I looked at previously, the Venari, as both rifles are fitted with a black tactical stock. Just like the one on the Venari, the GX-40’s handle is very well made, being incredibly rigid despite being hollow in certain areas as a weight-saving measure.

Gamo describes it as a “lightweight ergonomic tactical stock that offers superb comfort, alongside toughness that will laugh off the knocks and bumps in the field”.

The butt pad is not adjustable for height, and while it appears to be a ventilated style it’s quite rigid and offers no compression – not that you’d need any recoil-absorbing properties on a sub-12 foot pound PCP.

The stylish cheekpiece looks like it should be adjustable for height, but again the comb is set at a fixed height, which I found to be a shade too low for the scope I fitted, but more on that later.

The stock is a thumbhole design and the drop-down pistol grip is steeply raked and heavily stippled, making it comfortable to hold, while offering plenty of grip. Although there’s no dedicated thumb shelf, there is a gentle contour in the side of the stock which lets you adopt a thumb-up grip as well as the conventional wraparound hold.

The trigger guard is an integrated part of the stock, and it features an access hole so you can reach the rearmost stock screw. I found the rim of this hole to be quite sharp, rubbing uncomfortably on my middle finger when in the aim, so if the test rifle was mine I’d gently sand it down. However, other shooters who handled the gun did not experience this problem.

Despite the rifle coming in at just 3kg un scoped, the GX-40 is a full-sized rifle and the stock offers a long fore end, giving shooters the option to use whatever type of grip they wish with their leading hand.

The belly of the fore end is gently rounded, making it comfortable to rest in the palm of your hand, and with a scope on board the centre of balance was just in front of the trigger guard.

Features and function

The GX-40 has a blued barrel and air cylinder, which is evenly applied and looks like brushed black satin, while the action has been treated to a solid black finish.

The blueing isn’t as deep and lustrous as it might be, but is perfectly fine nonetheless. Like the Venari, the gap between the rear of the action and the stock has been filled with a black plastic insert.

The gently curved trigger blade is made of polymer, and has a smooth, flat face. The safety catch is located immediately in front of the blade. You pull it back towards the trigger to put it on safe, and while it can be applied at any time, I got myself in the habit of setting it before cocking the rifle.

The two-stage trigger is adjustable for both stages, but I prefer to shoot test rifles as they come out of the box, as not all shooters are comfortable adjusting a trigger, and so this is how they will likely be shooting theirs.

First-stage travel was long and light, followed by a positive stop point, while there was quite a lot of creep in the second stage. In time, I learned to predict when the trigger would break, after which I didn’t really have to think about it when shooting either at the range or in the field.

I wanted to fit a scope that matched the characteristics of the GX-40, offering decent performance and value for money, and chose a Hawke Airmax 4-12×40 which I attached to the rail using Sportsmatch mounts taken from the company’s slightly wider than normal 13mm range, which fit perfectly level on the Gamo rail.

Due to Gamo and its sister company BSA sharing the same magazine system, which does not stand proud of the rail, it’s easy to position the scope for perfect eye relief.

What wasn’t quite perfect for me was my eyeline, which was a little low due to the fixed height of the comb, but our physical make-up is all different, and this won’t be a problem for many other shooters.

Two calibre options are available – .177, as on the test rifle, and .22. As has already been mentioned, the GX-40 uses the standard 10-shot BSA magazine, with the internal rotor being colour-coded blue for .177 and red for .22.

Both BSA and Gamo multi-shot PCPs use a locking system to secure the magazine in the action, but while BSA uses a sliding catch, Gamo uses a magnet, which is admittedly quicker and easier.

The cold hammer-forged barrel is threaded 1/2” UNF and supplied with a muzzle brake-cum-thread protector. I did shoot the rifle with the muzzle brake in place, but found it a little too loud, especially when shot at my indoor range, so exchanged it for a 0dB moderator for the rest of the test.

Performance and precision

Air pressure can be monitored via a gauge at the end of the main cylinder, and a snap-on plastic collar protects the fill port. In keeping with many other Gamo and BSA PCPs, the gun can be filled to a maximum of 232 bar using the standard Gamo/BSA probe. (Read our list of the best airgun compressors.) 

You can often flatten the power curve on an unregulated PCP by filling to a lower starting pressure, but just as I found with the Venari, the GX-40’s curve was actually pretty flat from a full fill.

Gamo gives an estimated shot count of 60, but I managed to get 70 before accuracy noticeably diminished. This was a very pleasant surprise, as I always shoot conservatively and tend to end up taking fewer shots per fill than the suggested number.

I shot several types of pellet through the GX-40, including Air Arms Diabolo Field, Rangemaster Sovereign, Weihrauch Magnum and Rifle Precision, with these all shooting pretty well. (Read our advice on picking the best air rifle pellets .) 

However, this particular barrel seemed to prefer H&N Baracuda FT, with my best five-shot groups at 30 yards measuring around 3.9mm centre-to-centre, and averaging 6.5mm. Those are really impressive results for any rifle, let alone one of this price.

Back at 40 yards, group size opened considerably, hovering around the 2.5cm to 3cm mark. This might shrink with further pellet testing, but as it stands I’d be content with a maximum range of 35 yards for hunting.

The results over the chronograph were simply stunning, with the GX-40 returning an average muzzle velocity of 704 feet per second with the Baracuda FT pellets, a muzzle energy of 10.3 foot pounds and a velocity spread of just 4.1 feet per second.

With the benchrested testing phase over, it was time for some proper shooting. One of my favourite ways to shoot is standing using sticks, and the rifle’s relatively light weight combined with the long forend made it an excellent candidate for this type of shooting stance, while its neutral point of balance made it good for sitting and kneeling shots too.

The Gamo GX-40 is a budget gun, but rather than call it a starter gun, I think it’s better described as a capable air rifle that just happens to be inexpensive. Depending on your build, you may have to compromise somewhat when it comes to scope choice due to the non-adjustable nature of the stock, but one area you won’t need to compromise is accuracy.

The Airgun Shooter verdict:

• Look and feel: 8
• Stock: 7
• Build quality: 8
• Sighting up: 9
• Cocking: 8
• Loading: 9
• Trigger: 7
• Handling: 9
• Accuracy: 8
• Value: 9

Overall score: 82

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