Help with mods guys.

[44david44 43]

Bit of help guys just want to no what kind of mods I can get to up the proformance my hw100.I no the rifle has great proformance but want to make it outstanding.

Edited November 27, 2010 by 44david44

[ArchieHood 3,692]

I think the HW100 is pretty much as good as it gets,I think your only improvement on it is to trade it in for an Air Arms.

[Phantom 631]

The best Mod for a HW100 is.......

 

Practice

 

And a block 'n' tackle to help you lift it

 

Phantom

[44david44 43]

I think the HW100 is pretty much as good as it gets,I think your only improvement on it is to trade it in for an Air Arms.

Have an s200 and had an s510 be for I got the hw100.

[Buster321c 1,010]

HW 100 Improvements

 

 

The main culprit:

 

The breech block is sealed with a large 12x1.2 O-ring. For some reason HW have opted for a crush installation. The O-ring is pinched between breech block and action acting like a gasket seal, however, this prevents the two parts from mating properly and also allows some movement. This is perhaps only a couple of thou, but it's enough to cause problems, e.g. loose barrels (made worse by excess oil) sticking magazines and slow leaks. The O-ring is effectively destroyed upon assembly. Hans Weihrauch made a comment regarding an O-ring that always needs replacing during a stripdown, he didn't say which, but this is the one. Simply replacing this O-ring with a 12 x 1 and degreasing the front half of the action, including barrel and grubscrew (there's a lot of oil in this area) together with careful reassembly, will ensure you'll never suffer any of these issues again.

 

 

With the valve cap/breech block removed it's worthwhile making a quick inspection of the following:-

 

1. Check the valve seat for damage. Any scratches can be removed by catching a wad of Scotchbrite (grey/fine) or 000-0000 steel wool in the chuck of a twist drill and applying it with light pressure to the valve seat. The valve can also be cleaned by catching its stem in the drill and applying a wad of abrasive by hand. Be very gentle and try not to change the angle of the beveled edge/sealing face. Only perform this operation if the valve has scratches or debris embedded in its surface. Clean with a paper towel, lint free cloth or use a blast of air from your tank.

 

2. Valve return spring has closed and ground ends that can be quite rough. If you like you can polish the ends of the spring with 1200 grit wet or dry paper.

 

Make sure all the above components are absolutely clean and dry before refitting them.

 

3. Inside the breech block are two O-rings which seal the valve stem and pellet probe/bolt. These will only leak during the firing cycle and are not responsible for any slow leaks or loss of pressure(sizes listed below). A good tip for fitting the probe O-ring is to push a cleaning pellet up to the groove and manoeuver the O-ring into place from the opposite side.

 

The new main seal, 12 x 1, sits nicely in its groove and deforms under air pressure to seal, as an O-ring should.

 

Ensure securing bolts are free from excess oil and clean the threads with a brass brush. The breech block can now be properly secured and the main seal O-ring can even be reused, should you strip the rifle in future. Clean all oil from the barrel, barrel channel and grub screw. Make sure the grubscrew is dry and its threads are clean. The barrel can now be secured against the breech block - use the short end of an allen key to finger tighten it - the barrel will not loosen until you want it to. Do not use too much force when fitting a silencer. It seems the loose barrel issue worsened with the introduction of the screwcut MKII with heavy handedness when fitting a silencer being partly responsible. (Note: there is a trade off here, having the barrel and various securing bolts dry increases the risk of corrosion. An occasional visual inspection is recommended.)

 

Inconsistent power:

 

The heavy grease HW use on the hammer doesn't help re: varying power. Consider that most PCP's run with a dry hammer. This grease is dissipated through use, may be thinned if a lighter oil is introduced or changes in temperature can affect its viscosity. All affect the force with which the hammer strikes the firing valve. Degrease and lube the hammer and shuttle with a thin oil as it's steel on alloy. I'd also recommend cleaning up both to remove rough edges. Chuck up the hammer/shuttle in hand drill and give it a quick spin applying light pressure with 1200grit wet/dry. The hammer has a single circular bearing surface just in front of the rear spring guide/pip. You don't need to mirror polish either part.

 

On to the main valve; removed from the action with a deep 10mm socket, this valve consists of five components. Two threaded brass parts that make up the valve body and inside, a 4mm ball bearing (regulating valve) a spring and an O-ring. This O-ring is used to seal the two halves of the valve body. This O-ring doesn't appear on any parts diagrams/lists, size is 2x2. IMO this has too large a cross section and is pinched between the two halves of the regulator valve body reducing ID further. This reduced ID can interfere with the consistent seating of the ball bearing regulator valve. Simply replace it with a 2.57x1.78 (#005). Ensure the ball bearing is free from debris and grease/moisture from fingers. The O-ring is probably best fitted dry. The valve only needs to be re-assembled finger tight and just nipped up when replacing it in the action.

 

Igor Jelenski, who first suggested this mod, recommends trying a 3mm ball bearing and a stronger spring. If you\'d like to experiment with this I would also suggest sleeving the spring retaining portion of main valve with some 1/2mm PTFE sheet to keep the ball bearing centralized.

 

The regulator piston O-ring will, over time, take a compression set. As this is a dynamic seal this will result in leaks and erattic performance. It's simple to replace, the size is 7x1.5, same as main valve outlet.

 

Fine tuning:

 

You can make your own regulator output tester quite easily using a 1/8 BSPP female - 6x1 male tapered adapter. My gauge is from MDE and is 1/8 BSPP back entry. The male thread on the adapter is self sealing (if this isn't the case use some PTFE tape on threads). Drop an O-ring, 5.28 x 1.78 (#009), into the adapter before fitting the gauge. It should seal finger tight .

 

To use a pressure tester you'll need to remove the ball bearing from the test port located under a grubscrew. If it's stuck it can be pushed through from the inside with a small allen key (remove reg valve and piston to access it and be careful not to scratch the action).

 

Belleville washers that control the regulator\'s output can be quite dirty and may benefit from a clean and very light lube, just wet between fingers with a light oil. Stack as follows (())(())(())(())

 

The factory setting for the regulator output is approx 90 BAR. A slightly higher output pressure coupled with less hammer spring tension can increase shot count (lots of testing and patience required here) as valve duration is reduced as are the effects of hammer bounce. The increase is subtle and each gun is different. Barrel length and calibre also have to be taken into account, but off regulator velocity spikes can be avoided. Otherwise just stick to 90 BAR. If you don't have a pressure tester, make a note of the regulator's spring tension adjuster position before dismantling. Mark the 12 o'clock position on the screw (Tippex or WHY) and count the number of turns to remove it. Alternatively, measure the depth of the adjuster screw relative to the action. On my rifle, 90BAR is 2.82mm.

 

Finally:

 

It's worth noting if your gun loses pressure when stored and you're unsure of the source of the air loss, all slow leaks on the action can be fixed with 5 O-rings in just 3 sizes.

 

12 x 1 Breech block (once fitted it's unlikely this will leak again)

7 x 1.5 Regulator piston and main valve outlet

2.57 x 1.78 (#005) Main valve inlet and internal

 

Use pure Silicone grease on all O-rings except the main valve internal.

 

Tip: When removing old O-rings push a pin into the O-ring itself or use a new razor blade and be careful, don't try and dig under the seal as you may scratch the sealing surfaces.

 

Here's the full list of factory O-rings and the two recommended alternatives (bolded)

 

O-ring HW 100, 37.1 x 1.6 Cylinder clamp 2682C

O-ring HW 100, 15.6 x 2.5 Barrel clamp 2682B

O-ring HW 100, 32 x 2 Magazine 2603A*

O-ring HW 100, 13 x 2 Adaptor A 2704

O-ring HW 100, 2.57 x 1.78 Adaptor B 2703B

 

O-ring HW 100, 3 x 1.5 Valve stem 2655D

O-ring HW 100, 12 x 1.2 Breech block main (12 x 1) recommended 2658

O-ring HW 100, 5.5 x 1 Breech/probe seal .22 2659A*

O-ring HW 100, 4.5 x 1 Breech/probe seal .177 2659A*

O-ring HW 100, 4 x 1.5 Probe buffer 2618A*

O-ring HW 100, 2.57 x 1.78 Main valve inlet 2665D

O-ring HW 100, 7 x 1.5 Main valve outlet 2666

O-ring HW 100, 2 x 2 Main valve internal (2.57 x 1.78) recommended N/A

O-ring HW 100, 7 x 1.5 Regulator piston 2668

O-ring HW 100, 10 x 1.5 Tension adjuster (sometimes omitted) 2672

O-ring HW 100, 8 x 1.5 Barrel 2679

 

FX/V-Mach Probe, 5.28 x 1.78 PUR70

 

 

For more information and help ,

 

Cantact Pok or Nemo1966 on airgunforum.net

 

 

Have fun Buster

Edited November 27, 2010 by Buster321c

[Buster321c 1,010]

I think the HW100 is pretty much as good as it gets,I think your only improvement on it is to trade it in for an Air Arms.

 

 

 

Now there`s a man who knows his stuff

[hunter1989 91]

hi buddy

 

maybe a new owner

 

only kidding hw100 are as good as they get

 

atb steve

[Sweeney-Todd 208]

Bit of help guys just want to no what kind of mods I can get to up the proformance my hw100.I no the rifle has great proformance but want to make it outstanding.

 

 

 

Hi David.

 

Same here mate.....we need Tench to make one of his reg's for the 100

Mine crept up to 12.30 ftlb

After a chat with Simon ( Tench ) I have now got her back down to 11.6

 

ATB.

 

 

 

Bill.

[Buster321c 1,010]

hi buddy

 

maybe a new owner

 

only kidding hw100 are as good as they get

 

atb steve

 

Well engineered yes , excellent rifle again , yes .

 

 

As good as they get ? Sorry , i cant agree with that ... but as with all thing money dictates so that depends on what you have to spend .

[44david44 43]

hi buddy

 

maybe a new owner

 

only kidding hw100 are as good as they get

 

atb steve

 

Well engineered yes , excellent rifle again , yes .

 

 

As good as they get ? Sorry , i cant agree with that ... but as with all thing money dictates so that depends on what you have to spend .

What's your thoughts on the best rifle out there.

[Buster321c 1,010]

That can only be answered by way of identifying what it`s needed for .

 

A hunting rig would be no good if it was a Steyr LG 100 . The Steyr LG 100 is a precision target shooting rifle , how it would stand up to the bumps and scrapes in the field ? Not worth thinking about .

 

As would be the benefit of using a BSA Ultra for FT shooting . Again , not knocking the merits of any gun , but what it`s intended use ? This is the key for all shooter`s .

 

Daystate , fine rifles as are Ripley , and a whole host of custom`s avaliable to use these days .

 

At this moment in time , the best rifle`s for me are my MPR-FT , and my S410K ( regged ) . The S410 is a fine fit for me , and it suits all my needs , multi shot , light , like i say all i need at the minute .

 

The MPR is a way for me to venture into the HFT world a little . Again it`s not the best choise for targets , but i can combine it with my hunting rig and have a day rig , and night rig if i wish .

 

So for me , at the minute , those are the best rifles for me .