Webley and Scott Hawk Mk II

A blast from my early teens

After removing the rust from the Webley Hawk and taking a closer look at the name engraved in the top of the action, memories started to trickle in to my mind of using this air rifle as a teenager. Did my uncle have one he use to let me shoot up Lickey Hills?, or was it the one me and Paul Pedley used when we skived off school and take down Langly Mill to blast cans with? But there's no mistaking it, i have had dealings with this air rifle in my youth. So when this dawned on me it was a no brainer, this is the one to fix up first.

For now i just want to clean her up and reseal the piston and breech as the rifle was only putting out two ft/lb, if things look promising i might then invest in a new main spring, remove the paint and blue it, sand the stock, treat with oil and possibly varnish.

First i removed the stock which is held on with a philips head bolt at the front of the trigger guard and two longer philips head screw bolts that run 45 degrees upwards on the fore stock.

Webley Hawk Mk ll, the best Christmas present a big kid could get in the70's.

Using 0000 wire wool and gun oil i removed all the rust from the action and barrel, this left about 50% of the original enamaling that had not come off with rust and general wear. 

Looks almost respectable once the rust had been removed.

There was a long crack in the stock running from the end of the cocking slot to the side of the trigger guard, i eased the crack apart and let Locktite run into as much of it as i could then pressed together for ten minutes. This works amazingly well from past experience, and any excess gets sanded of when treating the stock.

 The trigger housing is welded onto the end of the compression tube, there are three pins that hold the trigger, sear, and the safety slide which are secured with circlips.

Removing the circlips then drifting the pins out allows the trigger and its tension spring to be removed then the sear, safety, and sear tension spring can slide out, i thought it best to take a photo so it would be easier to remember how to put it back together,

The tab that bends 90 degrees to hold the trigger in place on the safety slide had snapped off

The breech was loose in the forks so i drifted the pivot pin out and applied pressure to the forks in a vice in small stages,  using rubber inner tube to protect the metal.

The amount of old British air rifles from the 70's i have to do this to is unbeleivable

Now it fits nice and snug with no play what so ever.

No play in those forks any more

I don't know what it is about British air rifles not using Screw bolts for the breech pivot, it's one of the things that do let these excellent air rifles down.

A new breech catch spring might be in order, but the old one will do for now.

I was very careful to catch the breech catch pin and spring, but luckily it was not under to much tension.

I also noticed the .177 barrel was moving in the breech block slightly, this just needed a hex head grub screw on top of the breech block tightening to hold it firmly.

A hex grub screw holds the .177 barrel in place, two small hex bolts hold the rear sight on as well.

The Webley Hawk Mk11 came with two barrels originally you could interchange, but alas i only have the .177 with this one.

The end cap came of really easily as i was able to push the retaining pin out with no pressure on the end, the spring was in pretty bad shape at one end with zero preload overall.

Nice solid end cap, but a spring guide would help here for sure.

The piston is quite weighty so doesn't need a spring with loads of preload as a rule, and at first glance all lubrication had dried up.

One grubby piston with the knackered main spring next to it.

The whole of the inside of the compression tube was generally grubby along with all of its components.

The hand tells how dried and grubby it all was.

There are two piston rings made of PTFE or something similar, these had become very worn over the years and quite brittle. I broke one when i removed it but the other came out in one piece, they cost about £ 20 for spares so i think i will try rubber O rings. whether it's two O rings or one O ring and the undamaged PTFE ring, it all depends on which combination gives the least friction.

PTFE  piston rings beyond repair, 19 mm ID and 2.5mm thick. However a 17 mm ID x 2.5 mm rubber O ring makes a good replacement as the 19 mm ID was to big in rubber.

Now it was time to give the compression tube a clean with white spirits and OOOO wire wool, and definately scrub the piston down more importantly. Then white spirits on a cloth to remove any wire wool bits left behind, this was done with the aid of a rod and tape to secure the wool and cloth on.

White spirits and wire wool shift all grime, but does tend to struggle with disintegrated buffer washers on BSA's.

Now it was all nice and clean i spent the next hour polishing the compression chamber and piston with Autosol metal polish, it was well worth it as they were gleaming at the end of it.

Smooth and shiny inside and out, and a bloody aching arm.

I slipped two O rings onto the piston and tried to see if there was much resistance, though this was after i filed all the sharp edges off before i had cleaned and polished the rifle admittedly. The piston moved down the chamber with about two pounds of pressure, and moved a tiny bit and stopped still when i tried with my finger over the transfer port.
The transfer port was looking okay but i decided to rejuvenate it with some silicone grease, I also applied a smear to the piston O rings as well.

Logun silicone grease protects and rejuvenates rubber seals, ideally used on PCP's but it's always done my breech seals the world of good.

For now i'm going to make some slip washers and a delrin top hat and use the old spring, if it all looks good then i might invest in a new spring and treat the stock and metal work. So that's it for part one for now, part two will be real soon as all the rifle parts are sitting in a box on the kitchen table and getting in the way.

TTFN

Wing Commander Sir Nigel Tetlington-Smythe 

Longsroking the .22 BSA Mercury

After fitting a brand new Titan XS spring to the Mercury, I discovered that the recoil was a little fierce, so I thought it would be a good idea to take it apart and nip a few coils off. I also thought I would have a go at increasing the swept volume, as this had been recommended on some of the airgun forums I have read. As it stood, there was far too much preload, and when I fired it I could not follow through as the scope view bounced all over the place.


So there came a day when I had the house to myself, what better time to set about tinkering with a rifle! Out came the screws that held the stock on and the action was placed in a vice protected by an old glove.

Don't want to scratch the bluing any more than it already is.

Then I set about unscrewing the trigger housing with the use of an old metal bar.

Any old bar will do the trick.

Remembering the preload, I jammed a large heavy piece of wood behind the trigger unit so it wouldn't go flying through the shed wall when it came loose as I undid the rest by hand.

Just got to be careful here.

There was still a far too much preload. I could see 2 or 3 coils coming off this one.

That came off with some force all the same.

Moving back to the kitchen table to remove the guide rod, spring and piston. I first removed the cocking linkage guide so the the linkage could be removed from the piston.

As the cocking linkage is articulated, you can remove the guide to slip it out of the compression chamber with out removing the barrel.

Once the piston was removed, I could straight away see one reason for some inaccuracy - the buffer washer I had made up out of rubber washers had flattened and was rubbing along the compression tube. Just as well, that was the piece to take out to shorten the piston and long stroke the compression chamber.

Pin is out, piston head removed.

With the piston head removed by tapping out the pin, the washer was removed. Now I had to see how much of the front of the piston cocking rod had to be removed in order for the head to sit on the piston body.

See how much needs to come off the end of the rod.

It was no more than 2 or 3 mm as there was extra space in the piston head for the rod end to sit in, so a quick grind down on the lathe soon removed the excess.

After the grinding of the rod, mmmm shiny.

Next I took out the Dremel, (well, actually a cheaper copy made by Draper), which had the bits and bobs I needed to carry on with the job.

The Draper, which is cheaper than a Dremel, and the piston body after the rod has been shortened.

Using the Draper and a cutting disk, I then set about extending the cocking slot in the piston body, because with the buffer washer removed, the piston would slam into the cocking linkage if this was not done.

Extending the cocking slot.

I removed about 4 mm and smoothed it off with a grinding stone, making sure it was even so that both bars of the cocking linkage would connect with the piston slot. I thought it best that if I was shortening the piston by 4-5 mm that I should only lengthen the cocking slot by no more than that, that's how thick the buffer washer was.


Now I had to drill a new hole for the pin that connects the piston head to the piston body, this is most likely strongest if done at 90 degrees to the original.

Lining up where to drill hole.

I lined the head up with the body and marked off where the pin would go through. First I used the Draper to grind a center for the drill, then with a battery powered hand drill I started to drill a 3.5mm hole.

Grinding new hole for the pin.

I found I was getting no where fast as the post was hardened metal, however I did find some sort of metal grinding tool in the Draper parts and that did the trick nicely.

Strange grinding head that beat the drill bits.

The hole now completed and not crossing paths with the original hole, I tested it all lined up with a darts head, which it did nicely allowing me to tap the pin in.

The finished article.

With the piston completed, I applied the appropriate greases to the seal (abbey SM50) and base on the piston (abbey LT2), then inserted it into the compression tube which I had cleaned and polished up. With the piston fully inserted I tested to see if there was space for the cocking linkage, which when pressed flat along the compression tube was about 2mm.

It's dark in there, but there is a gap.

There would be more than this as there is a steel spring plate that holds the cocking linkage against the linkage guide, also the spring stops the linkage interfering with the mainspring.

Steel spring plate that holds the linkage up.

I have a belief that the preload shouldn't exceed the swept volume. This is not proven by me but picked up from articles i have read by people who know their stuff. So with this in mind I decided to remove 3 coils, which i did along with shaping the last coil on the mainspring.

With some Abbey LT2 grease smeared liberally over the spring, spring guide, and washers, the rifle was placed in the spring compressor along with the trigger bock, in the jig I had previously designed for it.

Parts back in line and greased up.

Titan XS are really stiff springs and even with 3 coils removed there was a fair bit of preload, so when the spring compressor started creaking and broke, I wasn't really that surprised!

Bugger! Broke the spring compressor!

I remembered it straining last time I worked on the Mercury and should have strengthened the screw housing then, but by supporting the trigger block and jig with one hand it still managed to work and I was able to give the trigger block that 180 degree turn so it would catch. Quick as you like it was out of the compressor and tightened by hand until the final touch, that involved the vice and the bar so everything lined up nice and tight.


With the cocking linkage slotted in and the spring plate in place, I screwed the linkage guide in place, then the stock and scope were finally fitted and the gun was ready to be tested.

Start putting her back together.

The recoil is nowhere near as harsh as it used to be, in fact it's quite pleasant to shoot now. I am finding that with using .552 Air Arms Diabolo fields, I can usually get sub inch groups at 20 yards with the odd flyer, though I am refining my hold again as I have been using pnuematics a lot lately and my springer shooting tecnique has slipped a bit.

Yet again I didn't get around to putting a top hat and slip washer in the compression tube and piston, but it seems to be performing very well as it is. Apart from the odd flyer which as I said is down to my hold, it is a mighty fine air rifle indeed and i'm pretty chuffed with the results so far.

I believe that the spring was too fierce and was causing too much air to choke at the transfer port giving harsher recoil. I have also read that some other people also increase the diameter of the transfer port when long stroking, so i'll have to see if it's worth doing at some point in the future. For now i'm going to be finding the best pellets to use with this air rifle, as these older British ones do have a slightly larger bore of 5.6mm.

TTFN

Best wishes, Wing Commander Sir Nigel Tetlington-Smythe.