Mk3 accuracy - seems to vary wildly

[andrewM]

Testing, as I have, two Webley Mk3 from the '60s, I was hard pressed to obtain 2 inch groups at 25 yds, using a selection of pellets - including old .22 (5.6mm) pellets. This was very disappointing.

Fortunately, my own two Mk3s both produce tight 3/4 inch groups at 25 yds (S.domes) - which is pleasing given that open sights are used.

I think it was Lakey, here, who advised me that 'button rifling' was introduced by Webley in the late '60s or early '70s. Given my Mk3s are late production, this tends to suggest that the later rifles benefitted from the improved barrels.

What about the earlier Mk3s? Are they accurate? Or is it a hit and miss situation, depending upon the production performance/skill on the day of manufacture?

I had been toying with the idea of adding an early Mk3 to my collection but it seems that accuracy is something of a lottery that cannot be depended upon. It seems that quality control in the factory, in this particular respect, was not at all good and this is surprising given the superb quality of the general appearance.

Despite cost cutting elsewhere, the last years of production do seem to have the benefit of good accuracy and perhaps these later products should attract a premium, if I am correct in my observations.

I am wondering what other owners have experienced.

Rgds to all Mk3 devotees!

A

[laverdabru]

That is an interesting point. I've got an early '60s Mk 3 in near mint condition, which is beautifully made & a pleasure to use. But not nearly as accurate as my early '70's one in similar condition.
I've found the same with my AirSporters of similar eras - the later one, although costcutting is evident, is far more accurate. But I think my early A/S has had a hard life.

[slug-gun]

No tap loader can ever be truly accurate due to the pellet having to 'jump' from the tap into the barrel. If you are lucky and you have a rifle where the tap and barrel line up exactly it will be better than one where it doesn't but that's about as good as it gets.
For this reason contemporary break barrels were often more accurate than underlevers. Until the advent of the sliding breech which moved things on hugely.

[Geezer]

Interesting.

I think it’s more complicated than you suggest.

A lot is down to the fitmet of the tap (better early, less good later).

Some may be ammo (5.6 nominal v 5.5).

And MkIIIs are old. Anything from 43-72 years: a lot can have happened (or not) in those years, varying from nothing at all (cue old solidifying grease) to various levels of use/abuse or poor servicing.

[andrewM]

Hmmm - some equally interesting replies.

Not least, laverdabru has reached the same conclusion. I think I am on to something here; the rifling changed and, with it, the accuracy improved. I wonder if anyone else has noticed this.

Can it be said for certain that the tap alignment deteriorated? I am not sure it did. One of the members here was involved in the factory and explained the method of aligning the tap which, due to its complexity rather passed me by but I don't think the method changed.

On the general point of tap loaders, my BSA Standards perform well - far better than the '60s Mk3s - and one is 97 years old.

[Farsight]

Have you checked for leaks ? Not only at the tap but the screws that attach the stock bracket to the receiver. Also check the leather piston washer for fit and condition . It's fixing screw which can also back out and become damaged.

Apologies if you've done all this already

Atb Mark

[slug-gun]

You're not getting the point here I think. It doesn't matter how brilliantly the tap was fitted etc, the design is inherently poor in terms of achieving really good accuracy. In their advertising Webley claimed that the MK.3 in .177 would group into 1.25" at 40 yards.

This level of accuracy is poor, and actually worse than could be achieved by a good shot. Ergo the shooter can never attain or achieve his/her true level of ability because the gun is not 'good' enough to allow him to do it!

A modern rifle, ie a pre charged or top quality (tuned) springer can shoot into 1/4" at 40 yards, (5 shots) when handled by aforementioned good shot. You could use a tap loader for ever and not get anywhere near this.

In 1988 Theoben improved the potential of the underlever greatly with the advent of the superb SLR88. Though this was a breech loader type design, it refined this system by adopting a loading probe which seated the pellet SQUARELY into the breech, and the same distance into the barrel also, both huge benefits in terms of good accuracy.

Further the probe was hollow and therefore the blast of air was centred into the back of the pellet for maximum efficiency. Coupled with a superb Anschutz barrel this was one accurate gun, probably the most accurate recoiling piston rifle ever made.

Even with pre charged rifles, they are more accurate when using a single shot loader, as like the SLR88, the pellet is entered square into the breech, to the same distance. Using the mag will reduce ultimate accuracy, especially if the mag is spring loaded as the spring can cause the pellet to be slightly twisted as it enters the breech/barrel initially at a slight angle.

Don't get me wrong I love Mk.3's and have owned dozens of them. They will last for ever, and are fun to shoot but can never be truly accurate.

[andrewM]

Thanks Slug-gun.

Was this Webley advertising from the '70s, I wonder, or prior to that? Certainly, there seems to have been an improvement in accuracy in the '70s and I would attribute this to the improvement in the rifling in the barrels.

I accept all that you say about the weaknesses of tap-loaders but my point and theory is that the earlier Webleys were even poorer in accuracy, due to poorer/inconsistent barrels at the time.

One might note that open sights do add to the complication in that they are less accurate than modern scopes.

Mark, yes, I checked all these points; the rifle was a friend's and I cleaned out and re-lubricated the piston, spring and leather washer.

[bill57]

Webley claimed that the MK.3 in .177 would group into 1.25" at 40 yards.

I'm sure they would be achieving this with open or aperture sights, scopes on air rifles were uncommon back then, and the scope rail on a Mk.3 is dubious at best. Also consider the pellets, compared to modern offerings?

I think you're unfairly maligning tap loaders. While I agree that if the tap alignment is not perfect accuracy will suffer, if the alignment is perfect then I don't see why they should be less accurate. It's a simple matter to capture and inspect fired pellets, and an examination of the rifling imprint will show whether they are clipping or not.

Apart from hunting, I shoot tap loaders almost exclusively these days, and I get better results with them than any other guns. I also suspect that shooting a 1/4" group at forty yards with a springer takes a bit more than just a "good shot".