Webley Senior
My new/old Webley Senior slant grip pellet pistol.

History of airguns

Part 1

This report covers:

  • First surprise
  • Surprise number two
  • Install the seal
  • Velocity before the seal
  • Velocity after the seal
  • Not the velocity test
  • Summary

This is another great one for the weekend. In fact, it’s a follow-on to last Friday’s report. Remember that one? That was where I showed you my new/old Webley senior air pistol. I told you that it needed a new breech seal, so a week ago yesterday (Thursday) I ordered a seal from T.W. Chambers in the UK. It arrived in my mailbox on Tuesday — just five days later.

First surprise

And that, my friends, is today’s first surprise. The breech seal I needed made it to Texas from England in five days! There is a guy on You Tube showing you his Webley Senior breech seal and he tells you they don’t make them anymore. Phooey on that! They do and they are as close as your computer. It cost me about $7.50 with shipping, so no big deal.

Webley Senior breech
Remember, this is where the Senior breech seal goes.

Webley Senior breech seal
And there is the seal.

Surprise number two

In the years since I have installed one of these seals they have changed. They used to be made of fiber and had a brass liner. This one looks like rubber and there is no liner. I think the rubber will hold its shape better than fiber, so it doesn’t need the brass liner.

Install the seal

If you look at the new seal you’ll see that one side is rounded and the other is flat. The rounded side goes in the hole first. I found it a lot easier to install than the older fiber seal. I used a large pin punch to press down the sides of the seal and they went in quite easily.

To install it I didn’t even cock the pistol. I just opened the barrel and went from there. There is plenty of access that way.

Webley Senior breech seal installed
And there is the seal installed. It stands proud for now, so be careful when closing the barrel on it. It will wear in.

Velocity before the seal

My plan was to give you the velocity before and after installing the seal, but pellets stopped coming out altogether so I couldn’t get the before velocity. Let’s just call it zero. The pellets did come out in my office at about 40-60 f.p.s. but I could have been using smaller 5.5 mm pellets. Let me show you what I’m talking about with an H&N Field and Target Special.

Webley Senior breech with FTT pellet
As you can see, the H&N Field Target Trophy pellet with 5.53 mm head falls deep into the breech.

Webley Senior breech with Eley Wasp pellet
The 5.56 mm Eley Wasp pellet fits the Senior breech much better, though many of them fall in just a little.

Find a Hawke Scope

Velocity after the seal

It is now difficult to close the Senior’s breech all the way, though it can be done. And when the breech is closed, Eley Wasps go out at around 340 f.p.s.

Webley Senior Wasp velocity
With the new seal in everything is better. Sorry for the blur, but I couldn’t use the flash because the chrono senses it and wipes out the display.

Not the velocity test

Today was not the velocity test. All we did today was install the seal and verify that it works. That puts us back on track for the remainder of the test that will be the same as always.


So far I have shown you a great find in a desirable airgun and today we saw how easy it is to fix. There is no need to tear the pistol apart for what we did. Next time we check velocity with different pellets in the usual way.