Webley Tomahawk heavy recoil

[robs5230]

I measured the stroke and it came out at 83mm.

The transfer port seems to be just above 2.5mm. A 2.5mm drill bit fits in there with a little bit of play. Unfortunately I dont have any other sizes to check and cant get my calipers in.

The transfer port is countersunk. Is that done at the factory, or has someone messed with it? Hopefully that wont cause issues

I think the piston seal might be slightly undersized. When I put a finger over the transfer port the piston slowly drops down. Am I right in thinking it shouldn't move at all when you cover the port? If so does anyone know a good replacement seal thats still made for Webleys?

I really wish I would have got it glided a few years ago. I remember my glided Longbow being amazingly smooth to cock. This is kinda rough to cock, despite using moly grease.


Thanks for the help guys, really appreciate it!

Try one of the purple seals from TW Chambers
They're very good and more efficient than the red Knibbs ones

I'd do that before anything else

[Mark A]

so 83mm stroke is not short.. if anything, for a 28mm (or are these 29?) bore, you have too much... this coupled with your port being around 2.5mm and your spring having low preload, your piston will be bouncing quite a lot

I'd open it up to 3.0 without a second thought. In fact I'd go to 3.2 or 1/8", but for that final operation I'd suggest a reamer. You are likely to end up needing a softer spring as a result, so you can still have some preload.

I also agree that your piston seal seems undersized/worn. strip it down and replace at the same time you open the port. Chambers and bagnall & K will do webley spars, as will any of the major spares suppliers.

Thanks a lot. I just measured the air chamber and its 27mm if that improves things?

Are the Ozzy seals any good?

@TonyL Yeah I am trying to work out what is going on there. It looks like its been machined, but I can't work out why.

@robs5230 Thanks, I'll check them out. Are they better than the Ozzy seals?

[Shed tuner]

Thanks a lot. I just measured the air chamber and its 27mm if that improves things?

Are the Ozzy seals any good?

@TonyL Yeah I am trying to work out what is going on there. It looks like its been machined, but I can't work out why.

@robs5230 Thanks, I'll check them out. Are they better than the Ozzy seals?

yeah, 27mm helps. but that port is just too small...

[robs5230]

Thanks a lot. I just measured the air chamber and its 27mm if that improves things?

Are the Ozzy seals any good?

@TonyL Yeah I am trying to work out what is going on there. It looks like its been machined, but I can't work out why.

@robs5230 Thanks, I'll check them out. Are they better than the Ozzy seals?

I think the Ozzy seals are crap

Just seen what pellets you've tried
JSB RS are worth a shot. I use them in all my .22 rifles. They have a lower start pressure than the ones you've tried so you'll get a different shot cycle

[Mark A]

I'll give the RSBs a try, and also grab a purple seal from Chambers.

The transfer port is a little scary to mess with as its not like I can ever replace the rifle if I mess it up. I'll try the new seal and different pellets first and then maybe find someone to send it to that has the right tools. I did have a look into it and it doesnt look hard to do, its just hard finding a long enough drill bit thats the right size for the reamer. They seem to go from 2.5 to 3, and any specialist sizes tend to be on the shorter side. Although I did find a 7/16 in a long length that might work.

Thanks for all the advice, its been very helpful! I'll report back once I try the seal.

[TonyL]

If the tuning gurus decide that that area around the TP really shouldn't be like that, I wonder if a competent engineer could get rid of that void and open the port up at the same time?

[maximus]

Its a shame that someone has countersunk around the port as the gun is no longer to its original spec. I think a relatively easy fix would be to countersink to suit a socket head screw then drill and tap out the port and fit a screw with a hole drilled through the middle to the desired port size and secure with locktite.

[Shed tuner]

the countersink isn't that big a deal.. sure it's a little lost volume, but not a killer. If it bothered me, I'd degrease thoroughtly and fill it with JB weld.

To the OP, just get a "long series" 3mm drill bit. For sure sounds like your seal needs replacing, but any port less than 3.0mm on a 12Fp springer, especially on a 27mm bore, just isn't going to flow efficiently, so you may as well do it when you have the piston out.

[Mark A]

It almost looks like the countersunk bit is an insert made from another material. If I try a new seal and other things and it still has the heavy recoil I might look into getting someone to sort it, but have no idea who does this sort of work now Vmach is gone. I believe Lyn only works on Weihrauch guns at the moment and I dont know if he does lathe work etc.

Chambers order placed and despatched at 8am this morning! Hopefully I should have it Monday. I also ordered a new breach seal just to have as a spare and some moly powder. I'm quite excited to try the new piston seal

Edit: Thanks Shed tuner, thats good to hear. I'll see how it goes after the seal replacement. I am very tempted to open the transfer port. I checked my 97, 95, Lightning and even my Cometa 300 and all have at least 3mm. I'll get a drill bit ordered as long 3mm bits come in handy for pre-drilling for wood screws if I end up chickening out

[Shed tuner]

Edit: Thanks Shed tuner, thats good to hear. I'll see how it goes after the seal replacement. I am very tempted to open the transfer port. I checked my 97, 95, Lightning and even my Cometa 300 and all have at least 3mm. I'll get a drill bit ordered as long 3mm bits come in handy for pre-drilling for wood screws if I end up chickening out

yup, 3.0mm is still very conservative. most people open up their HWs to at least 3.2, or 3.4.

[evert]

the countersink isn't that big a deal.. sure it's a little lost volume, but not a killer. If it bothered me, I'd degrease thoroughtly and fill it with JB weld.

To the OP, just get a "long series" 3mm drill bit. For sure sounds like your seal needs replacing, but any port less than 3.0mm on a 12Fp springer, especially on a 27mm bore, just isn't going to flow efficiently, so you may as well do it when you have the piston out.

I know that the Webley ports are considered small, but the heavy 27mm pistons and small ports gives a shotcycle I really like, especially on a well set up Vulcan (I use the purple Webley seal and Maccaris HW50/99 spring spaced up).

A shortstroke Tomahawk should be very similar to a Vulcan.
I'd go for the purple Webley piston seal and a spring with 14-14,5mm ID and 3-3,1mm wire.

[robs5230]

I can't see why a Tommy, wouldn't benefit from opening the TP out to 3.2mm, as the late great Topdog advocated for the Longbow and Stingray

Just opened up 2 of my Stingrays to 3.2 and its like night and day.

Opening up the TP, would also rid it, of some of that lost volume that the concave milling imparted

[Shed tuner]

I can't see why a Tommy, wouldn't benefit from opening the TP out to 3.2mm, as the late great Topdog advocated for the Longbow and Stingray

Just opened up 2 of my Stingrays to 3.2 and its like night and day.

Opening up the TP, would also rid it, of some of that lost volume that the concave milling imparted

couldn't agree more.

[Brano]

It's a real shame that someone has for whatever their reason started drilling the TP. Who knows why they've done it. I have a lovely Tommie which has a similar 'counter sink' but into the milled recess where the barrel shims sit in the breach block. This has been done after the rifle has been blued. It's neat and the only reason I can think for it is to act as a grease reservoir. Fortunately it's not visible and doesn't effect anything. A mystery all the same.

Going by your image the TP size looks correct and my Sidewinder has a TP the same size as my other Tommies.
It shoots lovely and uses the same SS piston you have. The difference being it has a delrin block inserted in the redundant 'cocking slot' sorry it's late and the correct name escapes me. This rides against the top of the cylinder. Then the front has a delrin band.
Also fitted is a Webley Venom power pulse piston seal. It's shoots lovely.
I don't have any experience of wider TPs but would be interested to try the modification at some point as @shed tuner suggests. Particularly if @Topdog advocated it as he was very much a guru when it came to the Longbow.

I can't imagine you'll find it difficult to get it running smoothly with a correctly fitting piston seal.
I would try not to let the 'alteration" bother you too much as I doubt it has any noticeable effect other than knowing it's there.
If I were in your position I'd use some cold blue so it's not so obvious.

The Tommie is a fine rifle but the Longbow has the edge IMO when it comes to shot cycle and handling, even when both are tuned by a professional custom house.

Hopefully you'll get it shooting sweetly without too much effort.

[Mark A]

You're very lucky to have a Sidewinder. I had a Longbow sidewinder in .177 and it was so smooth to cock and shot lovely. I sold it as I planned to get another in .22, but it was just when Webley went under and unfortunately I never managed to replace it. I saw this Tommy for sale a long while back and jumped at the chance to at least own one of the old Webleys.

I got my Chambers order today. Very good service from them to receive it so fast! The seal looks good and almost the same design as the Vmach seal. Its very tight in the chamber though and doesnt slide down on its own, even with the transfer port uncovered. Will I need to size it, or is it being a tight fit beneficial?