Courtesy of our friendly legal counsel:
Disclaimer:
Modifications made to this rifle were performed by an experienced professional airgunsmith.
And, proved safe in THIS gun.
No warranties are implied nor extended.
We have no control of what you do on your own.
If you do decide to make ANY modification to an airgun, be conscious of which elements are under force or pressure and realize that, even a "little pre-compression" or as little as 10 BAR's CAN cause SERIOUS bodily harm.
These modifications have not been reviewed, nor approved by Webley / Hatsan or any other brand
Again: Be careful! You are the only guardian of your health and safety.
Disclaimer:
Modifications made to this rifle were performed by an experienced professional airgunsmith.
And, proved safe in THIS gun.
No warranties are implied nor extended.
We have no control of what you do on your own.
If you do decide to make ANY modification to an airgun, be conscious of which elements are under force or pressure and realize that, even a "little pre-compression" or as little as 10 BAR's CAN cause SERIOUS bodily harm.
These modifications have not been reviewed, nor approved by Webley / Hatsan or any other brand
Again: Be careful! You are the only guardian of your health and safety.
Foreword: A Shakespearean Experience
When I was in 7th grade, my English teacher got us started reading "Romeo and Juliet" by William Shakespeare
It was intentional. The girls in the class went head over heels for the romantic parts and the boys were excited by all the swashbuckling and swordfighting that went on.
Almost at the beginning of the school year, Zefirelli's film came out. ROFL!
We made it our business to organize "group viewings" (one of the few ways to get the girsl in OUR class go out with us ;-) )
Of course, our teacher found a way to put into the tests all those parts that were NOT in the movie, ROFL!
And that is how it became obvious to all of us our "fatal flaw".
Our serious shortcoming. Our main defect. We trusted too much the film and some of us paid less attention to the literature behind it.
After the first three quarters, our teacher was kind enough to provide "remedial study hall", during recess, for all.
A true life lesson. Along 8-12th grades, we went on to seriously study MacBeth, Hamlet, and other Classic English works, and learned how to enjoy them.
She was a great teacher.
Since then (and I am talking 1971), this idea of "Fatal Flaw" has played a good role in my life.
"Everything has flaws", "We're all Human", "Perfect is the enemy of Good and Done"; all aphorisms that help us deal with life's challenges are formed at an early age.
So, when I find something that is "afflicted" by a fatal flaw, I look for ways to correct it without making it perfect.
Because things have to be finished, and perfection is a never ending quest.
And a quest this was going to be, LOL!
A friend asked me if I would consider looking at a Webley Tomahawk ("Tommy" for short) that he had obtained at a very good price with a pristine walnut stock and absolutlely no blemishes.
To put it mildly, those three things in the same sentence piqued my interest and I said Yes!
It was intentional. The girls in the class went head over heels for the romantic parts and the boys were excited by all the swashbuckling and swordfighting that went on.
Almost at the beginning of the school year, Zefirelli's film came out. ROFL!
We made it our business to organize "group viewings" (one of the few ways to get the girsl in OUR class go out with us ;-) )
Of course, our teacher found a way to put into the tests all those parts that were NOT in the movie, ROFL!
And that is how it became obvious to all of us our "fatal flaw".
Our serious shortcoming. Our main defect. We trusted too much the film and some of us paid less attention to the literature behind it.
After the first three quarters, our teacher was kind enough to provide "remedial study hall", during recess, for all.
A true life lesson. Along 8-12th grades, we went on to seriously study MacBeth, Hamlet, and other Classic English works, and learned how to enjoy them.
She was a great teacher.
Since then (and I am talking 1971), this idea of "Fatal Flaw" has played a good role in my life.
"Everything has flaws", "We're all Human", "Perfect is the enemy of Good and Done"; all aphorisms that help us deal with life's challenges are formed at an early age.
So, when I find something that is "afflicted" by a fatal flaw, I look for ways to correct it without making it perfect.
Because things have to be finished, and perfection is a never ending quest.
And a quest this was going to be, LOL!
A friend asked me if I would consider looking at a Webley Tomahawk ("Tommy" for short) that he had obtained at a very good price with a pristine walnut stock and absolutlely no blemishes.
To put it mildly, those three things in the same sentence piqued my interest and I said Yes!
The rifle arrived
Scope was added for testing
Because the stock was in such a pristine condition, my friend was wary of shiping the rifle complete.
I suggested he disassemble it and ship it in a take-down shotgun hard case.
He did so, and the gun arrived.
It was truly in excellent shape, except that it wasn't cocking and I was told it wasn't creating any pressure. It had a super-stout spring. Which was contrary to what I had read about the Tomahawks.
When I disassembled the rifle I found the cause: a badly 'upgraded' gun.
The fact that all the screws were socket type and all made for the same Allen wrench told me that someone had gotten inside the rifle and tried a "full customization".
Hmmm m m m m. . . . . so much for a "very good price" I thought, this was going to take some serious time and time is money.
But let's keep to the track:
I suggested he disassemble it and ship it in a take-down shotgun hard case.
He did so, and the gun arrived.
It was truly in excellent shape, except that it wasn't cocking and I was told it wasn't creating any pressure. It had a super-stout spring. Which was contrary to what I had read about the Tomahawks.
When I disassembled the rifle I found the cause: a badly 'upgraded' gun.
The fact that all the screws were socket type and all made for the same Allen wrench told me that someone had gotten inside the rifle and tried a "full customization".
Hmmm m m m m. . . . . so much for a "very good price" I thought, this was going to take some serious time and time is money.
But let's keep to the track:
Disassembly
The disassembly of the Tommy posed some problems:
First and foremost, ALL the cocking parts' pins were flared at BOTH ends.
There is no way to disassemble without affecting that arrangement.
For a manufacturer to "rivet" the pins on both ends either makes it clear that the product is disposable/hard to service, OR that they want the guns returned to factory for service.
The problem is that the first is not a smart way to sell the product and the second is doomed to failure in a globalized market.
Clearly, when the gun was designed, the idea of "Think Global/ Act Local" had not reached the designers frame of mind.
Now, when you look at the trigger, then the problem is the completely opposite one: pins are just inserted and "glued" in place with grease.
If you clean the trigger, pins fall out all by themselves.
So, disassembly starts by removing all the stock screws (4), then you are left with the whole barrelled action.
The "Muzzle-Brake" is well fit and unobtrusive, there is no rear sight, so the whole can go into the spring compressor.
At the rear of the action there are two closing pins on the block AND there is an additional screw retainer/standoff that acts on the closing block and receives the fourth stock screw.
To prevent the pins in the trigger "unit" from falling out, I taped the whole thing (after having a number of pins fall out in a disconcerting and very obnoxious manner):
First and foremost, ALL the cocking parts' pins were flared at BOTH ends.
There is no way to disassemble without affecting that arrangement.
For a manufacturer to "rivet" the pins on both ends either makes it clear that the product is disposable/hard to service, OR that they want the guns returned to factory for service.
The problem is that the first is not a smart way to sell the product and the second is doomed to failure in a globalized market.
Clearly, when the gun was designed, the idea of "Think Global/ Act Local" had not reached the designers frame of mind.
Now, when you look at the trigger, then the problem is the completely opposite one: pins are just inserted and "glued" in place with grease.
If you clean the trigger, pins fall out all by themselves.
So, disassembly starts by removing all the stock screws (4), then you are left with the whole barrelled action.
The "Muzzle-Brake" is well fit and unobtrusive, there is no rear sight, so the whole can go into the spring compressor.
At the rear of the action there are two closing pins on the block AND there is an additional screw retainer/standoff that acts on the closing block and receives the fourth stock screw.
To prevent the pins in the trigger "unit" from falling out, I taped the whole thing (after having a number of pins fall out in a disconcerting and very obnoxious manner):
Once the gun is in the spring compressor, and the tension has beeen taken up by the compressor, the closing block pins can be pushed out, the trigger "unit" taken out, and then, the screw stand-off/retainer unscrewed to remove the closing block.
The fact that trigger didn't cock was a big issue. I could find no really useful diagram of the trigger assembly and the springs, mostly torsional, had a very peculiar arrangement, so peculiar that I thought that it was impossible for a maker to put a trigger together like that.
The trigger design itself is several thousands years old.
It follows the Chinese triggers for powerful war crossbows.
And it has been used in airguns for MANY years under different names:
HW has the "Rekord", AA puts these triggers in the TX-200 and the ProSport, Walther Sport (before it stopped making spring-piston airguns), put the same design into the LGU and the LGV
So, it's not that design itself is at fault, it is the execution the one that has shortcomings.
The fact that trigger didn't cock was a big issue. I could find no really useful diagram of the trigger assembly and the springs, mostly torsional, had a very peculiar arrangement, so peculiar that I thought that it was impossible for a maker to put a trigger together like that.
The trigger design itself is several thousands years old.
It follows the Chinese triggers for powerful war crossbows.
And it has been used in airguns for MANY years under different names:
HW has the "Rekord", AA puts these triggers in the TX-200 and the ProSport, Walther Sport (before it stopped making spring-piston airguns), put the same design into the LGU and the LGV
So, it's not that design itself is at fault, it is the execution the one that has shortcomings.
Trigger parts arrangement. Note the little holes in the Piston Hook and the Retaining Lever, these holes "anchor" torsional springs.
In the Tomahawk, the piston is stemless, so the trigger has to "lock" the piston's body itself. This requires a VERY substantial (heavy) piston.
In operation it is very simple:
The piston goes back pushed by the cocking linkage pushing the cocking shoe, this pushes the piston hook back, this rotates the piston hook that then pushes down on the retaining lever, and that allows the sear to move up and lock the three parts in place.
To release the shot, the trigger blade (that is screwed into the trigger bar) moves the trigger bar upwards, thereby moving the sear downwards and allowing the retaining lever to release the piston hook.
The piston hook then jumps down under spring torsion and allows the piston to move forwards, thereby compressing the air that flows through the transfer port and propels the pellet.
Simple.
When one of these triggers fails to cock, it is either a broken spring, a missing spring, a bent piece, a damaged piece, or a misassembled piece. In SOME cases, all of the above may happen.
As explained above the problems were that the gun was not cocking and that, when it fired, there was no pressure.
Therefore, at the time of disassembly, I did not pay too much attention to the trigger and focused on the powerplant.
Let's finish the disassembly of the rifle.
In order to get the piston out, you should not "unrivet" the cocking llinkage.
Instead you should look at removing the cocking shoe from the slot.
To do this, you need to disconnect the barrel from the forks, and that is done by removing the barreblock axle screw that needs to have the locking screw removed first.
You need to start by ensuring that you have the right screwdrivers.
British gunmaking is famous for using thin, shallow slots that need to be fit perfectly to the driver or risk damaging the screws.
So, first remove the locking screw:
In operation it is very simple:
The piston goes back pushed by the cocking linkage pushing the cocking shoe, this pushes the piston hook back, this rotates the piston hook that then pushes down on the retaining lever, and that allows the sear to move up and lock the three parts in place.
To release the shot, the trigger blade (that is screwed into the trigger bar) moves the trigger bar upwards, thereby moving the sear downwards and allowing the retaining lever to release the piston hook.
The piston hook then jumps down under spring torsion and allows the piston to move forwards, thereby compressing the air that flows through the transfer port and propels the pellet.
Simple.
When one of these triggers fails to cock, it is either a broken spring, a missing spring, a bent piece, a damaged piece, or a misassembled piece. In SOME cases, all of the above may happen.
As explained above the problems were that the gun was not cocking and that, when it fired, there was no pressure.
Therefore, at the time of disassembly, I did not pay too much attention to the trigger and focused on the powerplant.
Let's finish the disassembly of the rifle.
In order to get the piston out, you should not "unrivet" the cocking llinkage.
Instead you should look at removing the cocking shoe from the slot.
To do this, you need to disconnect the barrel from the forks, and that is done by removing the barreblock axle screw that needs to have the locking screw removed first.
You need to start by ensuring that you have the right screwdrivers.
British gunmaking is famous for using thin, shallow slots that need to be fit perfectly to the driver or risk damaging the screws.
So, first remove the locking screw:
Now you remove the axle screw:
This allows the barrel and block to be removed from the forks.
There are TWO washers located in "wells" on both sides of the barrel block.
One of them is flat, the other is slightly convex
There are TWO washers located in "wells" on both sides of the barrel block.
One of them is flat, the other is slightly convex
This ensures that you do not have to "cowboy" tighten the forks to achieve a good friction fit of the barrel to the action.
Once you have removed the barrel/block from the action, the linkage can be extracted and you end up with a free cocking shoe.
Once you have removed the barrel/block from the action, the linkage can be extracted and you end up with a free cocking shoe.
Now the piston is free to slide out.
This is what we found:
This is what we found:
The piston seal actually just broke into pieces once the piston was out:
Luckily, the piston had not been damaged:
And, the piston showed relatively little use:
One thing that became painfully obvious was that whoever attempted to "pimp" the rifle had used too long screws in the forearm, as the connecting bar was scarrred:
So, the pistion seals were ordered and, in the meantime, I looked at the trigger.
To start with, it is funny that all the parts are shifted to one side.
As I've mentioned when I received the gun, it wasn't cocking, and I found that the springs were not really doing their jobs.
Upon disassembly of the trigger section one part became painfully obvious had had some problems:
As I've mentioned when I received the gun, it wasn't cocking, and I found that the springs were not really doing their jobs.
Upon disassembly of the trigger section one part became painfully obvious had had some problems:
This is the safety plate, it is on the other side of the trigger, opposed to all the other moving parts, and, clearly, t had been banged.
So, we corrected that deformation:
So, we corrected that deformation:
The trigger bar was also interesting:
There is a nylon insert between the two trigger adjustment screws.
That insert serves as a "thread-locking"' device that prevents the trigger screws from moving away from their set positions.
That insert serves as a "thread-locking"' device that prevents the trigger screws from moving away from their set positions.
After quite some time, I managed to get the trigger back in working mode.
The piston seal had been received and so, it was installed:
The piston seal had been received and so, it was installed:
The piston was tried in the compression chamber, but there was absolutely no way it would travel the whole stroke.
So we decided to measure the inside of the compression chamber.
We broke out our bore measuring tool and after calibrating it, we proceeded to make some deep measurements:
So we decided to measure the inside of the compression chamber.
We broke out our bore measuring tool and after calibrating it, we proceeded to make some deep measurements:
It was a complete let-down.
The compression chamber measured 27.48 mm's at the "mouth" but only 27.00 at the bottom of the stroke.
There are precious few things a gunsmith can do with a conical chamber.
One is to change the piston seal to an ORing. That will take this difference in stride without loosing compression. But the owner did not want this, so what we did was to increase a LITTLE the frontal slot in the piston and sized the piston VERY carefully:
The compression chamber measured 27.48 mm's at the "mouth" but only 27.00 at the bottom of the stroke.
There are precious few things a gunsmith can do with a conical chamber.
One is to change the piston seal to an ORing. That will take this difference in stride without loosing compression. But the owner did not want this, so what we did was to increase a LITTLE the frontal slot in the piston and sized the piston VERY carefully:
It took over 10 tries to get it JUST right.
With a "proof" spring (a spring that is designed to test functionality, but delivers 3 ft-lbs, tops), the piston will not go all the way to the bottom.
Was this unexpected? Not really. British literature has labelled these guns as "seal burners" , and with a normal procedure that would be real. With the way we fit the seal, we have given the seal some "room to compress" but not enoug to "set" at the diameter required to travel to the end of the compression chamber. At the same time, the "lipped" design of the seal will still do its job at all points in the compression chamber.
Thanks should go to Jim Maccari at ARH for providing seals with a good fit and made from a great material.
We polished both ends of the piston:
With a "proof" spring (a spring that is designed to test functionality, but delivers 3 ft-lbs, tops), the piston will not go all the way to the bottom.
Was this unexpected? Not really. British literature has labelled these guns as "seal burners" , and with a normal procedure that would be real. With the way we fit the seal, we have given the seal some "room to compress" but not enoug to "set" at the diameter required to travel to the end of the compression chamber. At the same time, the "lipped" design of the seal will still do its job at all points in the compression chamber.
Thanks should go to Jim Maccari at ARH for providing seals with a good fit and made from a great material.
We polished both ends of the piston:
We checked the OEM guide and found it had a peculiar design.
Checking the Titan XS fit guide, we should have used a Titan # 8, but the owner did not want full power, so we opted to use a Titan #10, which is the same spring that is suggested for the TX-200 and the Pro-Sport.
We assembled the gun taking care to glue flat washers to the forestock's screw wells:
Checking the Titan XS fit guide, we should have used a Titan # 8, but the owner did not want full power, so we opted to use a Titan #10, which is the same spring that is suggested for the TX-200 and the Pro-Sport.
We assembled the gun taking care to glue flat washers to the forestock's screw wells:
We had already "slugged" the barrel and it had been clear that the barrel was a bit oversized, AND had NO CHOKE.
The British Airgun Pundits asign to this the issue of "seal burning", but I am not so sure about that.
It's a "largeish" bore and unless you have access to pellet heads in the 4.53 range, most pellets are loose.
With or without a choke, this is a problem waiting to happen. The "rail speed" that the piston can achieve without proper resistance from the pellet in the rifling will burn some seals.
So, with this knowledge at hand, we tested pellets with a known wide skirt and with "big heads"
Just to show a picture of the pellets' pass-throughs:
The British Airgun Pundits asign to this the issue of "seal burning", but I am not so sure about that.
It's a "largeish" bore and unless you have access to pellet heads in the 4.53 range, most pellets are loose.
With or without a choke, this is a problem waiting to happen. The "rail speed" that the piston can achieve without proper resistance from the pellet in the rifling will burn some seals.
So, with this knowledge at hand, we tested pellets with a known wide skirt and with "big heads"
Just to show a picture of the pellets' pass-throughs:
From left to right: H&N Baracuda Green, JSB 8.44/4.53, JSB GTO
Do notice that, while all the pellets have rifling marks at the head, there are virtually no tell-tale ring at one of the skirts, that tells us that the skirts are not completely obturating.
The H&N BG shows a SLIGHT ring, as well as the GTO, but the JSB does not
In this case, one of the possibilties is to use a very lightly constructed pellet, that will obturate under pressure.
The H&N BG shows a SLIGHT ring, as well as the GTO, but the JSB does not
In this case, one of the possibilties is to use a very lightly constructed pellet, that will obturate under pressure.
On the left, a fired JSB 8.9, on the right an unfired version of the same pellet.
Do note at the very base of the fired pellet how the skirt DOES show the obturation ring.
Chrono MV's showed that, while not the most efficient pellet, the JSB Xpress did show higher consistency:
QYS 8.49 grs.- 788 ± 4 fps
H&N B.G..- 812 ± 7 fps
JSB GTO.- 860 ± 5 fps
JSB Xact 4.53.- 782 ± 4 fps
JSB Xpress.- 793 ± 2 fps
Using this information, we tested at 15 yards:
Chrono MV's showed that, while not the most efficient pellet, the JSB Xpress did show higher consistency:
QYS 8.49 grs.- 788 ± 4 fps
H&N B.G..- 812 ± 7 fps
JSB GTO.- 860 ± 5 fps
JSB Xact 4.53.- 782 ± 4 fps
JSB Xpress.- 793 ± 2 fps
Using this information, we tested at 15 yards:
Not bad for a break barrel, huh?
And so, the gun was packed and shipped, and the owner and the gun lived happily ever after.
.
.
.
Hmmmm, nah!
After only a few shots, the gun stopped working altogether.
"Double, double, boil and trouble, fire burn and cauldron bubble!"
(Cue in Evil Witch laughter)
And so, the gun was packed and shipped, and the owner and the gun lived happily ever after.
.
.
.
Hmmmm, nah!
After only a few shots, the gun stopped working altogether.
"Double, double, boil and trouble, fire burn and cauldron bubble!"
(Cue in Evil Witch laughter)
The 2nd Round
The rifle arrived back in one piece.
I took it apart and realized that the trigger had malfunctioned.
Do note that in the Tommy, the trigger "unit" can be taken out without disassembling the powerplant.
I happily disassembled and put together the trigger properly and got it working.
Shot a test group.
Frustration should be the name of this picture:
I took it apart and realized that the trigger had malfunctioned.
Do note that in the Tommy, the trigger "unit" can be taken out without disassembling the powerplant.
I happily disassembled and put together the trigger properly and got it working.
Shot a test group.
Frustration should be the name of this picture:
First shot smack in the middle, and then, all flyers? LOL!
Not a group, more like a shotgun pattern.
The owner also said that he thought the shot cycle to be a bit "harsh", so, we needed to do something
We disassembled the gun and this is what came out:
The owner also said that he thought the shot cycle to be a bit "harsh", so, we needed to do something
We disassembled the gun and this is what came out:
Yup!
The Patented OEM guide had torn out and broken:
The Patented OEM guide had torn out and broken:
We talked it over and we agreed to create a telescopic Rear Guide-Front Guide/Top Hat arrangement.
A rear guide was turned from Delrin incorporating a Teflon thrust washer, and a Telescoping Front Guide/TopHat was turned from aluminum.
A rear guide was turned from Delrin incorporating a Teflon thrust washer, and a Telescoping Front Guide/TopHat was turned from aluminum.
Not the finished product, but you get the idea.
The whole thing was fitted and tested, and we now directed our attention to the trigger, this is what we found:
Apologies for the shakiness of the video. It is hard to hold the trigger in one hand, the camera on the other, AND trigger the trigger LOL!
Still I hope you can see that the Retaining Lever goes completely out of place rotating far more than it should
Still I hope you can see that the Retaining Lever goes completely out of place rotating far more than it should
This is where the Retaining Lever should stop
This is where it ends when uncontained
And THIS is the Tommy's "Fatal Flaw".
I do not know if something is out of place or missing from THIS gun.
It may well be that whoever did the "stoning" to smooth the trigger pull shortened a part too much, or perhaps this stock is overly "ample" in the trigger well. There are many possibilities.
It is clear that the whole architecture depends on something that is not there.
When you put together the gun this is how the area looks like:
I do not know if something is out of place or missing from THIS gun.
It may well be that whoever did the "stoning" to smooth the trigger pull shortened a part too much, or perhaps this stock is overly "ample" in the trigger well. There are many possibilities.
It is clear that the whole architecture depends on something that is not there.
When you put together the gun this is how the area looks like:
IF the intention was to stop the retaining lever from going overhead completely by using the stock well, then it is hard to justify such a large tolerance in the stock well.
IF the Stand-off / 4th stock screw was supposed to keep the retaining lever from going haywire, then the spec was wrongly drafted.
In any case, the "fix" was not as difficult as it would seem.
A simple shim to fill the hollow was all that was needed.
IF the Stand-off / 4th stock screw was supposed to keep the retaining lever from going haywire, then the spec was wrongly drafted.
In any case, the "fix" was not as difficult as it would seem.
A simple shim to fill the hollow was all that was needed.
3 mm's thick, cut to size, PVC shim
It worked like that, but it rattled, LOL!
So I glued it to the stock's well:
So I glued it to the stock's well:
The gun went back together without a hitch, and we proceeded to test again with a number of pellets:
SURPRISE!
Yes, it was a BIG surprise.
Same pellets, same shooter, same barrel, same spring; just the two piece telescoping guide.
30-40 fps more
10-13% more energy at the muzzle.
AND, more important, the energy level is more or less the same across different pellet weights.
It is also worthy of note that these were the first 100 shots for the new powerplant. So, some "settling-in" is expected as the parts "wear themselves in together" and the uniformity of the MV's and ME's should go back to whatever was "normal" for this gun.
It would have been interesting to test for accuracy the AA Fld Hvy, but, alas, the project had to end.
Gun was packed and shipped back to its owner.
Yes, it was a BIG surprise.
Same pellets, same shooter, same barrel, same spring; just the two piece telescoping guide.
30-40 fps more
10-13% more energy at the muzzle.
AND, more important, the energy level is more or less the same across different pellet weights.
It is also worthy of note that these were the first 100 shots for the new powerplant. So, some "settling-in" is expected as the parts "wear themselves in together" and the uniformity of the MV's and ME's should go back to whatever was "normal" for this gun.
It would have been interesting to test for accuracy the AA Fld Hvy, but, alas, the project had to end.
Gun was packed and shipped back to its owner.
Keep well and shoot straight!
HM
HM
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