Air Arms - Supplement We only produce a supplement for the Air Arms range of rifles in the power bracket of 10-14ft/lb. 14-19J, as we only get customers require help and advise for these guns in this power bracket. Firstly, please be aware that the regulator we have supplied is exactly the same design and specification whether it be for a .177 S200 at 3ft/lb. - 4J in Itally or a .50cal Dea-Sung at 177ft/lb. - 240J in the USA. The soul difference being the Body Case shape and size to suit the reservoir of each make and model of air gun. A regulator only supplies a pre-set air pressure to the Outlet Valve Chamber / Assembly, nothing more or and nothing less. It is not used to adjust the power or a air gun. Both power and efficiency (shot count) are governed by the tuning of the individual air guns Outlet Valve Assembly. This tuning also effects shot to shot consistency, although consistency is also largely governed through use of good pellets, with the main factor being pellet sizing and only selecting undamaged pellets to shoot. It would be wonderful if we could say to you ‘Do exactly A, B, X, Y, Z and your done’ but we cannot as each gun is different. Over many years of production Air Arms air guns have altered slightly in Hammer Travel / Weight, Outlet Valve Head Size etc. When you have such high air pressures on the Outlet Valve Head, very small difference in the Hammer - Weight & Travel, Outlet Valve Head Size, Outlet Valve Spring Compression & Transfer Port Size make a Huge Difference from gun to gun. You could swap the same regulator between three guns and find they vary enoumously. This is why we charge £195. for basic fitting and £245. for full custom fitting, due to the time and effort required to rebalance the Outlet Valve Assembly. All we can do is try to give you the very best starting point ‘Best Average’ we can from the years of knowledge we have gained. The Air Arms is great air gun, however there are two main factors that cause people issues when it comes to fitting a regulator, so I shall mention these first. All air guns become far more finely balanced once a regulator is installed, but with the Air Arms their combination of Hammer Weight / Tavel, Outlet Valve Size etc. mean that slight adjustments often make a large difference to air efficiency, in comparison to many other air guns. The biggest issue is power adjustment, for on the vast majority of PCP’s you can adjust the power finely by the use of a Hammer Spring Compression Adjustment Screw (Normally at the rear of the action). Sadly the Air Arms doesn’t have one of these screw or provision to fitting one. Neither does it lend its self to packing the Hammer Spring to increase Hammer Spring Compression via washers. Power is finely adjusted by a combination of altering Outlet Valve Spring Compression and Transfer Port Restriction. This isn’t the best solution.

‘So why do people get in a mess with the Air Arms?’

The primary reasons I believe is thus: People believe that you just put the regulator in and away you go. This means that they neglect doing a number of ‘VITAL THINGS’. The main one being ‘Not

Increasing Outlet Valve Spring Compression’ as advised in the regulator instructions manual. A: They do not do a full fill (200bar) down to (80bar) power graph of the gun, in conjunction with keeping a record on the air pressure in the reservoir at the same time and so they have no start point to work and tune from. B: They do not make any effort to fill in or keep records of the guns settings as they take it to bits, by this I mean fill in the chart on the last page of the regulator instruction manual. C: With reference to ‘B’ above the Hammer Weight is pretty consistent, and so it the Outlet Valve Head Outer Diameter, but it is ‘VITAL’ that you keep a record of Transfer Port Size or Restriction by the Adjuster Screw and ‘100% Paramount’ that you measure the force required to open the Outlet Valve 2mm when the air gun is empty of air, Hammer Travel from cocked to striking the Outlet Valve Stem is quite important too.

‘Why are these things important?’

These records are very important for two reasons: 1, They are important for you so as you can always go back to square one with your tuning. 2, If stuck an Airgun Smith can try to give you proper advise based on proper facts and graphs are 100 times better than strings of numbers.

Air Arms Air Rifles - Where To Start Over the years I have tried various bits of advise for Air Arms regulator fitters, as you will see from the Transfer Port Sizes chart in the General Instruction Manual - ‘The only Gun with it’s own advise!!!!!’. However having been an onlooker watching friends fitting and taking note of their issues - My advise on where to start is thus: 1: For future reference you first need to do a graph of the air rifles power output / In conjunction with the pressure in the air reservoir. Firstly fill your rifle to 200bar and record the shots down to 80bar. For the most accurate pressure reading, leave the rifle attached to your Pump or Dive Bottle once filled up (Close Bottle Valve) and record the pressure off of the gauge on the Pump or Bottle as the pressure falls with every 10 shots. Combine the Shots & Pressure in a graph. 2: As you strip your rifle make sure that you take notes and fill in the Chart on the last page of the General Instructions Manual. Pay particular attention to: A: Size and restriction of the Transfer Port. Usually the port is 3-3.1mm and 1/4-1/3 restricted by the 3mm Power Adjuster Screw B: Force in lb. or kg required to push the Outlet Valve Open 2mm when gun is empty of air. You can do this very simply by using kitchen scales. Leaving the Hammer on the guide rod and put a plastic tube over the hammer and then press it down upon the scales, taking note of the force to Outlet Valve movement. Usually the force required to move the Outlet Valve 2mm is in the region of 4lb. 4oz = 1kg 927g C: Hammer Travel. .Usually the Hammer Travel is about 8.80mm

Settings That I Would Use When Starting To Regulated An Air Arms Air Rifle A: Regulator: Leave the regulator as sett .22 95bar 1378p.s.i. / .177 105bar 1523p.s.i.

B: Outlet Valve Chamber Volume: Leave the Outlet Valve Standoff Spacer provided a loan (16-22mm Long).

C: Transfer Port Diameter: For .177 enlarge your transfer port to Advised 3.50mm (Maximum 3.80mm). For .22 enlarge your transfer port to Advised 3.50mm (Maximum 4.10mm). Note: The transfer Port goes all the way from the Outlet Valve to the Barrel and so the Outlet Valve Black, Breech Block and Barrel holes all need to be enlarged. If the power is a little to high we can and you can still use the Transfer Port Restrictor Screw to adjust the power down as required.

D: Compression of the Outlet Valve Spring: Remove the Old Brass Measuring Pot and Outlet Valve Spring and fit the New Outlet Valve Spring and Outlet Valve Spring Adjuster in its Place. Screw this in until the force / energy required upon the Outlet Valve Stem end is increased to 11lb. 4oz = 5.20kg to push Outlet Valve open 2mm when the rifle is empty of air. If you are going to lighten your Hammer then set it at 8lb. 8oz = 3.85kg instead. With our Outlet Valve Spring .75mm Com or Decompression = 1lb. = .453kg

Use a plastic tube in conjunction with a pair of kitchen scales.

For Your Records Chart It is best practice to try and keep as many records as you can, as they may come in of great use at a later date or on another project. This is how I record the load or force that the Hammer is under when in the cocked. I simply remove the Outlet Valve Assembly (Brass Spring Adjuster, Outlet Valve Spring & Outlet Valve). I then insert a 4.00mm X 150mm Long silver Steel Rod (3mm to 4mm Metal or Carbon Rod can be used as well)

taking great care not to scratch or damage the Outlet Valves Seating Face that is down within the Alloy Action Block. I push on a hard surface so as to push the Hammer back into the cocked position. Then using a suitable set of scales, I press on the rod watching and feeling when the Hammer is lifted off of the sear. On a Standard sub 12ft/lb Air Arms this will normally be about 11-11lb 8oz - 4.98-5.21kg. After regulating this figure should be a little less 9lb 12oz 10lb 8oz - 4.42-8kg.

E: Compression of Hammer Spring: With these setting we often find that the guns fps / mps is a little higher than we require and so it is common for us to reduce this by cutting the hammer spring down gradually, often ending up by removing between 1 & 1 - 2/3 coils. We can then use O-rings between the Spring & Hammer as packers to put power up. Note: If you do not wish to do this or do not think you are competent enough to cut the Hammer Spring Down and reform the end, then you can lower power by either Increasing Outlet Valve Spring compression or Use the Transfer Port Power Adjuster Screw.

F: General Good Practice: Clean and polish the Hammer Guide Rod. C l e a n a l l t h e r i fl e s components and fit any new seals that are required at the same time as installing the regulator.

Professional Workshop Owners: G: Hammer Travel: If you have facilities and capabilities to do so, Shorten Hammer stroke to about 6.6mm. Do this by making and fitting a Longer Outlet Valve Stem. Note: May require you to add Hammer Spring packing, or fit a Harder Shorter Hammer Spring.

H: Hammer Weight: If you have facilities and capabilities to do so, You can lighten the Hammer to 30-33gm from the average 45-47gm. Note: Lightening the hammer will usually reduce feet per second by about 10-15fps.

Air Arms Owners - Assembly Supplement Screwing The Reservoir Together The most important thing with the Air Arms reservoir cylinders reassembly is putting the Outlet Valve Stand Off Spacer in place correctly. The rifle needs to be assembled in a vertical manner. Firstly measure the distance ‘A’ From edge upon the Outlet Valve Body where the reservoir screw up to, To the end of your Outlet Valve Stand off Spacer. Make sure that you have inserted the Regulator into the reservoir, so as the front face of the regulator is a distance of ‘A’ - Minus 3mm e.g. A = 38mm - 3 = 35mm’ from the edge of the air reservoir cylinder. If you have pushed it to far use a screw to pull it back a bit (Screw size M3 / M4 / M5 depending upon model). Next hold the Outlet Valve Body vertically, with the Brass Pot facing upwards towards the sky, and the back of the action block (Hammer Guide Rod / Trigger) is pointing toward the floor. Lightly hold the Outlet Valve Stand Off “Centrally” onto the Outlet Valve Body with a little of the S i l i c o n e G r e a s e . Importantly look down from the top and check / double check that it is centrally aligned. Then holding the Action Outlet Valve Block assembly ‘Dead Still’ & ‘Vertical’ at all times, Screw the reservoir down onto the Action Out Valve Block assembly.