Webley and Scott Hawk Mk ll, part2

So here is part two, but not as soon as i would have liked. 

Sorry, but there is loads of stuff to do before Xmas.

Having already made a good piston head seal with two Rubber Orings There are a few things to fix still before she is any where near her former glory, also i would like to see if using one rubber O ring gives better compression through less friction. But for now lets do two O rings and different main springs and breech seals if needs be.

Two under sized O rings are stretched to make the perfect seal.

The main spring is pretty well worn but luckily it is the same one that is used in all the Relum models, and i have three of those sitting around so one would make a better replacement till i can afford a new one. There is no spring guide in the Mk ll's and lll's, and that is why the spring was so warped down by the end cap. The metal tab on the safety slide has snapped off, so the safety doesn't work, spot welding a new piece on and grinding to shape would work, but i'll maybe leave it as is for now.

Zoom in on this one to see the broken bit of metal that was the safety tab.

The stock is most definatly off a Mk lll because when i compared the Chamber's diagrams of all three Mk's, i could see the end cap was the shorter Mk ll, and the stock has the cut out for the longer Mk lll curved end cap with the safety to the side. 

Stone me, the stock has got the safety cut out for a Mk lll. ie. There fore i think, i'm bodged.

Some one had chiseled out the space for the safety tab at the rear of the Mk ll end cap, also the front sight is not a Mk lll and for all i know the barrel and front sight could even be off a Mk l.

Okay, it's not the rear sight. But is the front sight not a solid bit of kit. 70's Britain for you. And it also is a dead give away to the fact that it's a Mk II.

 Most annoying though is the fact that the rear sight doesn't adjust for windage, but with a bit of research i'm sure i'll get that sorted eventually.

The Hawk was sitting in the corner of the kitchen, so i had better get it together sooner than later

So it's time to get the Relum main springs out, shim the breech seal if necessary, and see what this little pup can do. Second hand spares should be pretty plentiful i reckon, because if you where a kid in the 70's you either had a Hawk or a Meteor. Unless your mum paid weekly for a Relum from a Kay's catalog, and there are bloody no end of Relums Knocking about.


I knocked up a small top hat out of delrin to give the old spring a little boost, i would have liked to have made a short spring guide but i was now out of delrin.

Oooh look, bendy spring. But it's got a top hat.

 I then took out all sharp edges in the compression tube with a small grinding bit in my Draper mini drill, then gave it another good clean out. 

Seriously now, if you don't want to damage your seals, just grind the hell out off every inside edge.

Smearing some Abbey SM50 between the two O ring seals the piston slipped into the chamber a lot easier now, and just before the piston finally went in i applied a decent swab of Abbey LT2 grease around the end. The piston moved down the tube with the slightest bit of assistance now, and stop dead when i put my finger over the transfer port. Now that is the sort of seal i want in a springer, one that seals air tight but creates as little friction as possible.

Abbey LT2 grease liberally smeared over the top hat and old spring and in that went, followed by the end cap which went on with a small amount of pressure by hand allowing the pin to slip in.

Preload with original spring and top hat.

The trigger safety, sear, and tension spring were put in the housing and with the aid of a small screw driver were aligned so the pins went in, followed by the trigger and it's tension spring which just left the circlips. Greasing the breech, breech detent, and spring i pushed the breech into the forks and lined up the pivot pin holes, 

Breech, Breech detent, Spring, and forks.

I put the geased pivot pin in one side of the forks and pushed down on the compression tube and barrel till the pivot pin holes aligned so the pivot pin pushed all the way through.

Lots of pushing, shoving, jigging, and tapping and it's all back together. Someone said, 'measure twice, cut once'. I say, 'just tap gently'.

 Sweet, the rifle's back together and all i needed to do was put the stock on.

I really don't know what this picture is doing here but it looks the part.

I took her out to the shed and put her over the chronoscope, using H&N field trophies which sat deep in the barrel i got an average of 6 ft/lb. This was good, with a decent spring and a new or shimmed breech seal i hope to get 10.5 ft/lb which was what they did from factory.

Highest power i could get with the original spring and two new rubber O ring seals.

Life moves on and several days later i take the spring out and replace it with the spring from my old stockless Relum Telly, i had to take out the trigger and safty catch in order to take the spring out.

There you go, Relum without a mainspring and a hawk with a beefier mainspring. This was done while i cooked dinner for my wife.

 With the longer stiffer spring out of the Relum the Hawk is a lot firmer to cock, this is an addition of six coils taking it from 31 too 37 and two inches of preload. I used the repaired spring compressor with the thread directly on the bottom flat half of the end cap, i could of built a wooden block to support it but it was easy enough just supporting it with my hand. I forgot to get a picture of this as i was cooking dinner at the same time, so i hope i explained it well enough.

Well slap me with a kipper, the stronger spring boosted the muzzle velocity to 9 ft/lb with 7 grain wadcutters and 8ft/lb with H&N trophies, you can't say that is not a result.

Well you have heard my crap enough for now, lets just look at some pictures of a freshly semi tuned rifle barrel and a chronoscope.

Premier's never let you down, i should really get some magnum's as they are not so heavy as these mother's

Two ft/lb if not more of an improvement.

For some reason i can alway's  depend upon these bugger's  for never taking me over the legal limit. But if you put them in a PCP, watch out.

7 grain, just like hobbies and always the one to test by.

Not too bad for a heavy pellet out of a springer, but Crosman's will come up trumps every time.

Oh, the variation, oh the different pellets. Oh lets just put a new spring in her and see what that does, at 9 ft/lb she is shooting well sweet for a .177 with an old Relum spring.

Here you go, 10 FPS faster than the lower out put with thes wadcutters and neigh on 9 ft/lb.

Well now, here's a number if you can read it, one of many with Webley.

Lots of numbers make your air rifle one of a kind.

 All i know about air rifle serial numbers is that with my Air Arms PCP Shamal,  the first 65 were prototypes, making mine the 6th production model.

I just thought i had to mention that as it is one of the prime movers in my air rifle collection, and she is running as sweet as the day she first fired a shot in the hands of her new owner. I really hope i can get the Hawk Mk II back to it's former glory, along with the extra barrel, original stock, and it's original power output (If not more).

Oh Goat's Testicals, I've already said goodbye.

TTFN.

Best wishes, 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. 

Tuning the Norica Quick

Seeing as i was passing on the Norica to my mate i thought i would give it a bit of a tune up, besides i needed to drop the trigger pull a bit as well so kill two birds with one stone. Also it would give me a chance to see how the spring compressor would work out, i reckon there must be some preload as it is quite heavy to cock.

Preload is from the start of the wider trigger slot

The first thing i did was to check out the exploded view on Chambers http://www.gunspares.co.uk/shopdisplayproducts.asp?id=24977&cat=Quick, this makes life so much easier. Two plastic tabs either side of the fore stock revealed screws facing diagonally up into the cylinder block, and two screws on the trigger guard the rear one connecting stock to cylinder removed the stock. The safety latch was connected on to the trigger guard, pushed in place by the cocking linkage when cocked. The trigger unit held a nut for the rear screw and two pins held it in place to support a washer, spring guide, and the main spring. The rear of the trigger unit protruded from the cylinder by one millimeter and when pushed flush removed the two pins, however the unit could only be removed by pushing the washer and guide unit forward and slide it forward and out the wide long slot in front of it.

spring and washer pushed forward and trigger unit slipped out forwards

Handy device for removing trigger block and then letting spring and all free

I made a tool from two fat lengths of ali bar bolted to a half inch length of copper pipe which i hammered square, the bars would then fit between the outsides of the trigger unit and the inside of either side of the cylinder. With the cylinder supported on the spring compressor by using parcel tape of all things, i was able to wind the washer and guide forward two inches so i could tease the trigger unit out through the slot. Unwinding the pressure off the spring soon started to become a little alarming as the compressor was fully unwound and still under tension but i could push this by hand and slip it off, it would seem that this air rifle has four inches of preload and six if i included pushing it forward for removing the trigger unit.

Held down by loads of parcel tape

Handy device being slipped between trigger block and cylinder walls

I removed the guts or the rifle which was pretty dry except for a spot of oil behind the nylon piston seal, it all seemed in pretty good nick apart from where the piston had rub a little on top of the cylinder. however the end of the main spring had not been ground flat, and the sharp ends had left a ring of tiny marks on the top hat and the metal washer on the inside of the spring guide. The mainspring itself was in near new condition but where the sharp edges had nicked the tophat and washer there were minute flecks of metal scattered about, the piston was heavy with an inner sleeve which was a tube with cocking and sear latching cut into the outer layer.

Spring as it came out of rifle

Both ends ground down flat and polished

Right then, what did i do? Oh yes now i remember. First off i ground down flat both ends of the spring and gave them a polish, then  sanded the washer and tophat with wet medium then fine wet and dry' then polished with OOO wire wool the tophat, spring ends, and washer that all connected with each other. I then cleaned out the piston cylinder with white spirits and wire  wool on the end of a piece of dowel then polished and cleaned out any old crap left in there with a J cloth on the same dowel. Mmmmm shiney smooth. The piston was polished before the seal and at the end, and all deburring was done with my trusty Dremmel.

Heavy polished top hat and piston seal

this is one heavy piston i can tell you

Putting Abbey SM50 oil around the base of the piston seal and Abbey LT2 grease of around an inch at the end of the piston i slipped it back into the cylinder, LT2 grease on the end of the tophat and slipped that in the piston, the spring was then liberally coated in LT2 and then inserted making sure both ends had a tad extra grease applied was put in, then the spring guide and washer was smeared with a little extra LT2 grease and popped into the main spring.

Just some handy shit to have around for tuning

Before reversing the whole process of using the special tool to slip the trigger unit back into the slot in the cylinder i used the Dremmel to grind the sharp edges off the sear and piston, but only a little as i did not want to mess it up big time. Carried on putting the Norica back together and put the scope back on, which with the stop on it should not interfere with its previous POI.

spring pushed back in so trigger block can be replaced

Out in the back garden and took a five shot group, though sometimes i perfer a ten shot group. Anyway the trigger pull was down and there was most definately room to take more off, and the grouping was tighter and three inches above point of aim which means that it is now putting out more power. The rifle was also not so hold sensative, which i would call a successful tune indeed. What more could you ask for, i am indeed one happy little marsupial.

As i said i could lighten the trigger some more, but i shall leave that up to my mates discretion . Me personally, i would take it down a lot more but then i am used to being spoilt on Record triggers

TTFN

Best Wishes, Wing Commander Sir Nigel Tetlington-Smythe DOA OBE MBE FOAD