HW 100 (All Models)

roll over the image to zoom in

HW 100 (All Models)

reward points

Product details

If your HW100 is fitted with a A&M cylinder you will need to included your original Weihrauch cylinder with the rifle. The Tench regulator is designed to fit the original cylinder or our lightweight cylinders only, it will not work with the A&M cylinder.

Main Work 

Tench Regulator & Tune (Includes a full service)

The Tench Regulator & Tune packages are designed to make your rifle more consistent and air efficient, not more powerful. All sub 12 (non FAC) rifles are set to around 11.5ft/lbs after any work is done, keeping you well within the legal limit. 

As well as fitting a Tench regulator and tuning the rifle we also engrave the breech block with the words RAT WORKS as a way of showing that your rifle has been regulated and tuned by us, this is free of charge. If you would like extra engraving please select from the drop down menu and you will be charged accordingly. 

When the work is done by the RAT Works the action is extensively worked on to increase the performance, efficiency, accuracy and overall feel of the rifle. Almost every aspect of the rifle is modified, changed or enhanced in some way. Below is a list of all the work under taken as part of the tune. Your breech block will also be engraved with RAT Works as part of having a Tench regulator and tune.


Fill Pressure when Tench Regulated



100 Carbine




100 Rifle




100 Bullpup (Short)




100 Bullpup (Long)




Hammer Mechanism

- Ensure the assembly is free of any oil, grease or debris which can cause consistency issues

- Polish the bearing surfaces in the hammer

- Hammer latch/trigger sear face modified if needed

- Hammer stem is modified to run more efficiently

Loading assembly

- Loading probe modified on some earlier models for better airflow, pellet feed and smoothness

- Bearing surfaces cleaned, and correctly lubricated

- The magazine locating pin is modified to give a smoother movement

- Lubricant is added to parts of the assembly to allow a smoother action

Exhaust valve, transfer port & barrel

- The exhaust valve stem assembly is modified to run more efficiently

- Valve is refaced if needed

- Breech face modified if needed to prevent damage to pellets while loading

- Crown of the barrel re-cut the to increase the rifles accuracy

Trigger assembly

- Sears are inspected, and cleaned of debris, should there be any damage or poor finish the faces are polished to a smoother finish

- Trigger let-off is set to a comfortable and safe amount.

After the regulator is fitted and the tune carried out you can expect a shot to shot consistency of single figures as soon as the rifle has been worked on. A worksheet/invoice will be emailed to you once work is complete detailing the shot to shot consistency through our SKAN chronograph, the rifle is held correctly in a mount to guarantee accurate results. This consistency will improve further as the rifle is used.

Full Service 

The full service strips and rebuilds your rifle replacing all seals and renewing any worn parts to revamp performance while sorting any problems you may have such as leaks, low power, poor shot count or other faults. 

Additional Options

Complete Lightweight Cylinder

A complete lightweight cylinder includes one of our lightweight cylinder bodies, which is 50% lighter than the standard cylinder body and brand new quick fill unit with our Rat Works gauge built in. The replacement quick fill unit will still allow you to use your standard HW100 fill probe

Lightweight Cylinder Body

This is a replacement for the standard HW100 cylinder body, less than 50% of the weight of the original, the feeling of balance and weight of the rifle is dramatically reduced.

Rat Works Gauge & Quick Fill Unit 

Replacement for the standard HW cylinder end, or replacement for the old MK1 Cylinder end that was a gauge only. This unit allows you to fill using the standard HW100 probe. 

Rifle Collection & Return Service

We can arrange a collection and return service from you via our fully insured next day courier if you are not local to us. This service allows air rifles to be collected and returned to your home address on a fully insured next day service.


1. We will only need the action/metalwork of the rifle, no stock, silencer, scope or shroud etc.

2. If applicable, please include the magazines or magazine you prefer to use with the rifle, if you have ever had any problems with them and we can investigate as required.

3. Please ensure the rifle is not cocked or loaded when packing for shipping! Rifles can still be charged with air.

4. Do not ship in a case/bag or with stock still attached (except for stock engraving or spring rifles) Shipping with these will incur a £25 storage/re-shipping charge.

5. Pack the rifle in a plain, strong cardboard box preferably with adequate newspaper or bubble wrap packing and mark the box with FRAGILE and DO NOT AIR UPLIFT.

6. Collection can take place any time between 09:00 and 18:00 on the day, we cannot specify a time unfortunately.