Weihrauch HW 40 PCA Owner’s Guide

The HW 40 PCA is one of the easier air pistols to own, mainly because there’s no compressor or pump to think about. This guide covers how the single stroke system works, cocking, loading, the trigger and safety, and how to keep the seals in good shape, everything worth knowing before you take it out for the first time.

How Does A Single Stroke Pneumatic Pistol Actually Work?

When you cock the top section of the HW 40 PCA, you’re compressing air inside the pistol itself rather than drawing from a stored reservoir. That’s the whole point of the single stroke design. You only get one shot per cock, so there’s no topping up or multiple pumping involved. Once you fire, you simply cock it again for the next shot.

That’s also why filling equipment never comes into it, which is worth spelling out clearly if you’re moving over from a PCP rifle.

Do I Need A Pump Or Compressor For The HW 40 PCA?

No, and this is the biggest thing that sets it apart from a PCP rifle. The HW 40 PCA runs on a single stroke pneumatic system, so there’s no separate air tank to fill and no pump or compressor to buy. 

Every shot is self contained, you cock the pistol once per shot and that single stroke builds all the air pressure you need to fire.

What Calibre Is The HW 40 PCA?

Weihrauch manufactures the HW 40 PCA in .177 (4.5mm), .20 (5.0mm) and .22 (5.5mm), though in practice it’s most commonly available in .177. Check with us on current stock if you haven’t ordered one yet, since not every calibre is always held.

Always use diabolo pellets, never steel darts, ball bearings or anything else, and don’t reuse damaged or previously fired pellets.

With the basics covered, here’s the cocking and loading process itself, step by step.

How Do I Cock And Load The HW 40 PCA?

Hold the grip firmly with one hand. With your other hand, hold the top section just behind the rear sight so it can’t spring up on its own. Draw the hammer back, then lift the top section and swing it forward in a smooth circular motion until it stops. This action automatically engages the safety, so you don’t need to do that separately.

With the top section open, load a pellet into the barrel so it sits flush with the end. Then push the top section back down, using your thumb to make sure the hammer snaps shut properly. At this point the pistol is loaded and ready to fire, so keep it pointed in a safe direction and disengage the safety only when you’re ready to shoot.

What If I Need To Decock Without Firing?

If you’ve cocked the pistol but haven’t loaded a pellet and need to decock it, press the muzzle firmly against something soft like a mat or piece of cardboard, then pull the trigger.

Never try to force the top section back down without doing this, and never let go of the top section partway through cocking since the built up air pressure can make it spring open unexpectedly.

Can I Adjust The Trigger On The HW 40 PCA?

The trigger has a single adjustment screw that sets the pull point, turning it left shortens the travel before it releases, turning it right lengthens it. It’s a fine adjustment, and even a small turn makes a noticeable difference to how the trigger feels.

The factory setting is a good starting point for most people, and Weihrauch’s own guidance is to leave it as supplied. If you do want to fine tune it, small changes at a time are safer than one big turn, and if you’re not confident doing it yourself, a qualified airgun gunsmith can do it properly in a few minutes.

How Do I Line Up The Sights On The HW 40 PCA?

Line the top of the front sight up level with the top of the rear notch, with even gaps of light on either side, then centre that sight picture on the middle of your target. Keep both eyes open if you can, since it makes it easier to stay relaxed and track the target.

It takes a few sessions to build consistency, so don’t worry if your groups are scattered at first.

Once you’re loading, aiming and firing comfortably, the last thing worth building into your routine is looking after the pistol itself.

How Do I Look After The HW 40 PCA So It Keeps Its Power?

The seals are lubricated at the factory when the pistol is assembled, and Weihrauch’s own guidance is that this shouldn’t need topping up under normal use. If you ever notice a drop in power or a sealing problem, that’s the point to get it looked at rather than trying to fix it with oil yourself.

Beyond that, always make sure the pistol is unloaded and decocked before you clean it, and never attempt to strip it down yourself. The internals are under pressure, so any repair or reseal needs to go through an authorised dealer or back to Weihrauch directly.

Is There Anything Else Worth Knowing As A New Owner?

Treat the HW 40 PCA like any other airgun, always assume it’s loaded, always point it in a safe direction, and keep your finger off the trigger until you’re actually ready to shoot. The safety catch is a mechanical aid, not a substitute for careful handling.

Store it unloaded and decocked, and keep it out of reach of children.

Once you’ve got the cocking and loading routine down, the HW 40 PCA is about as low maintenance as air pistols get, no compressor, no fuss, just pick it up and go.