by Tom Gaylord
Writing as B.B. Pelletier

Part 1

A history of airguns

Webley Senior straight grip
Webley Senior straight grip air pistol.

This report covers:

  • Lubricated
  • Breech seal
  • Velocity — Eley Wasps
  • JSB Exact RS
  • RWS Hobby
  • Cocking effort
  • Trigger pull
  • Evaluation so far

Several readers liked Part 1 of the report on the straight grip Webley Senior. What did they like about it? They liked that the gun was made of steel. They liked how quirky it is. And, much like me, they liked it just because it exists. Well, today we’ll start learning how good it shoots.


There is more to this gun than just its historical value and charm. I told you in Part 1 that I replaced the breech seal and lubricated the action after I bought it around 1978. I have oiled it over the years, but never fully lubricated it since the first time. Later in this series I’ll disassemble the gun for you and show you the insides, but for now know that the piston serves as the mainspring guide and the pistol is sealed by a metal ring, much like the piston of an internal combustion engine.

I want to check on the lube after 38 years! Yes, it’s been that long since I applied it. Finally I will have a concrete example with some age that let’s me show how long these modern lubricants can last. And, yes, I plan to show you, as well.

Breech seal

The breech seal is different than most spring gun breech seals and I will show you what it looks like when the seal for my Webley Mark II Service rifle finally arrives. I wanted to shoot that rifle for accuracy for you, but until the breech seal is replaced I think it’s pointless. We would only wonder what it would do with a good seal.

These breech seals are deeper (longer) than conventional seals, and they have a hollow brass tube running through their centers that serve as the air transfer port. They can be made of either leather or fiber, and as I remember, the one in this pistol is fiber. The gun is running at a very conservative power level, so the seal has been under no particular strain, other than the years it’s been in the gun.

Velocity — Eley Wasps

Let’s look at the velocity, shall we? First up is the pellet I think matches the gun’s own vintage age — an Eley Wasp. This is the 5.56mm pellet that’s oversized for most modern pellet guns. In this pistol, though, they stop level with the breech after being dropped in.

Wasps averaged 310 f.p.s. over 10 shots. The low was 301 and the high was 316, so the spread was 15 f.p.s. For a vintage .22-caliber spring-piston air pistol this is a very good velocity. I’ve seen vintage Dianas do less. Next I think I’ll try a lighter pellet that’s more modern.

JSB Exact RS

The .22-caliber JSB Exact RS dome weighs 13.43 grains, compared to the Wasp’s 14.5. It falls deep into the breech, so its smaller as well as lighter. I expected to see somewhat higher velocity. But it wasn’t there.

Ten RS pellets averaged just 306 f.p.s. The spread was tighter, only 10 f.p.s. separate the low at 301 from the high at 311 f.p.s. I don’t know what that suggests. Maybe they will be more accurate, but I get the feeling the Senior wants more to push against. Let’s try a lighter pellet that I know is larger than the RS.

RWS Hobby

At 11.9 grains the .22-caliber RWS Hobby is a little lighter than the RS, but the skirt is also larger. It falls into the breech only slightly deeper than the Wasp. And the velocity surprised me. The average was a whopping 357 f.p.s. and the spread was 24 f.p.s. — from 343 to 367 f.p.s. I have the feeling at out to 10 meters the Hobby may hold its own for accuracy.

Cocking effort

The way the Senior cocks, it is extremely difficult to measure the cocking effort. And the effort changes drastically when you hold the barrel differently. I use the thumb of my left hand as a fulcrum, opposite the pistol’s own fulcrum at the barrel pivot. I will estimate the effort is between 15 and 20 pounds to cock the gun, which is a close as I’m going to get. It’s not quite as difficult to cock as a Beeman P1, which cocks in exactly the same fashion, though with improved cocking geometry.

Trigger pull

I have never before measured the trigger pull of this pistol. I only know that I like it a lot. If you pull the trigger slowly and deliberately, the effort is 5 lbs. 5 oz. That’s heavier than I thought. Heavy, but oh, so smooth!

Evaluation so far

The test is turning out pretty much as I thought it would. The gun has a lot of power for its age and powerplant, plus the recoil is almost nonexistent. There is zero vibration, so I will have to look at the old lubrication carefully. I doubt it can be improved upon.

The trigger is as nice as I remembered, but heavier than I thought. The smoothness masks the pull nicely.

Will the gun be accurate? I don’t know. I know I’ve shot it at things in the past, but we are talking many decades since I shot it seriously. In that time new pellets have come to market and it will be interesting to see if they have had any affect.