Why is the HW95 so bouncy??

[maximus]

The best thing about this thread is the idea of a shoot off between the 85/95 and the D34/36/38. Very interesting.

Ideally, add in some others, like the 80 and FWB Sport.

This can be arranged as I have 177 80 and a new sport in my collection. I might do a warts and all set of 5 x 5 shot groups for each rifle and see how we go.

[TonyL]

This can be arranged as I have 177 80 and a new sport in my collection. I might do a warts and all set of 5 x 5 shot groups for each rifle and see how we go.

Ah, that'll be something to look forward to seeing.

So, when you started this thread off, did you envisage it becoming the epic classic that it has become?

[PCPShooter]

My favourite 95 combo is a v mach tuned one (which probably involves a tad of TP widening to match the shorter faster spring) coupled with a heavyish mod - EB Sirocco or PH, with a scope of 50mm AO objective as this meets my cheek position best and I feel indulged in the nice wide angle of view often afforded.......

When set up optimally a 95 in any cal is smooth and pleasant to shoot at uk power, and not jumpy

Would I like a 95 with too small a tp port and too much soft spring -nah
One with a lightweight hw mod where balance is off and barrel won't hold on target - nah

I haven't shot a new Diana 34EMS version, but the last gen 31/34 T0-6 Dianas with sorted internals are indeed just as nice as a well sorted 'stage 1' 95 imo with their tp just about right from factory as it goes

[averageplinker]

Some interesting views throughout the thread. Interesting that a lot of stock is held in the feel of a rifle; I seem to recall BTDT noting on here or in his articles in the mags that a smooth cycle is no good if the accuracy is poop (not his exact words mind )

[Geezer]

Some interesting views throughout the thread. Interesting that a lot of stock is held in the feel of a rifle; I seem to recall BTDT noting on here or in his articles in the mags that a smooth cycle is no good if the accuracy is poop (not his exact words mind )

He has indeed. And I think he’s right.

I prefer the completely dead firing cycle of a Giss gun to the FWB sledge thing. But it’s the FWBs that won the Olympics and internationals.

I quite intensely dislike the typical Theoben rammer’s firing manners. But they hit what they are aimed at, better than a lot of guns with more pleasant shot cycles (yes, I appreciate that there are a bunch of other variables at play).

I can think of other rifles that shoot well (in terms of hitting targets), but are snappy or twangy, or jumpy.

The HW77 combined high accuracy with a smooth cycle (especially compared to the quite lively FWB Sport which preceded it as FT rifle of choice).

It’s hard to underrate the influence of the HW77 35 years ago on our thinking about springers even today.

I wonder if part of the 77’s influence was to persuade us that smooth cycle = accurate, when it’s actually a lot less simple than that.

[Geezer]

A final thought today on springers. Maybe needs a different thread.

The consensus on here is that the original factory 12ft-lbs versions of things like the HW80, D48/52, Webley Tomahawk, D460, etc, are really bad because they retain a 16-20+ ft-lbs piston and long stroke, but use a soft weak spring (and on the 48/52, a TP restrictor) to reduce power and have a long slow lazy cycle. And are inefficient, which means loads of wasted energy.

And therefore that to get the desired quick, smooth, action, you need short-stroking or sleeving or other major internal changes.

And, yes, I’ve shot some of those and they range from nice to VERY nice.

Thing is, in my limited experience, the factory jobs actually shoot quite well. Not brilliantly, but not anything like as bad as you might think. Even the D48/52.

And they did in the past (although a lot of 1980s “12ft-lbs” HW80s were 40-50% over the limit).

One explanation might be that the weight of the 80 etc helps a lot. But the original Tommie isn’t heavy. And the D48/52 is staggeringly inefficient but still accurate.

My hypothesis is that slow inefficient actions benefit from the slowness, because the excess energy not used to propel the pellet is absorbed by the gun and shooter over a longer period of time, reducing its effect on accuracy.

On a similar theme, the FWB Sport is odd. Set aside its poor trigger group and weak lock-up. And that while it handles well (I think brilliantly, but I’ve owned them since 1982, so I am completely used to them and can’t be objective on that front) it is light and muzzle light. It breaks the “rules”. Long stroke is good, but four inches of preload? The Diana 45 feels similar: an action that is a long way from the ideal, but has/had a great reputation for accuracy.

[TopDog]

Some interesting views throughout the thread. Interesting that a lot of stock is held in the feel of a rifle; I seem to recall BTDT noting on here or in his articles in the mags that a smooth cycle is no good if the accuracy is poop (not his exact words mind )

Spot on!! As a little exercise some while ago I did some recoil tests with my Test 80, light hold, firm hold, butt held firmly against cabinet (semi-rigid) and butt held firmly against wall (rigid). Will dig those out and post a collage of the results overlaid!

Action liveliness is of no real consequence as long as it, and the rifle/shooter interface, is the same every time. That, I think, is the essence of a springer and why they are so much fun to shoot! I always turn to springers for pleasure, the PCPs are for the clinical work!

atvb
David

[TonyL]

Yes, above all other qualities or traits, accuracy has to be the #1 goal.

[robs5230]

There's quite a lot wrong with the 95 out of the box.

The factory setup is pretty poor. They've just bunged a spring in with the hope of it being safe at sub12 (once the factory lube has burned off). But before the lube has all been combusted, the efficiency of the factory seal will have reduced, by it being hardened by the combustion.
Inefficient seal - harsh shot cycle. Thats if the seal hasn't already been compromised on assembly, by being rammed past the razor sharp cutouts in the cylinder, by some bloke in the factory.

Barrel length - now 310mm. Supporting the now accepted fashion for silencers on springers, and also compromising efficiency, with the shorter barrel producing less power.
The 410 barrel with the muzzle weight, being more efficient can produce a far softer shot cycle.

Lots of methods have been commonly used and described on here to "tame" the 95. Most just masking symptoms and making them appear better.
Obviously a set of well fitting guides will reduce twang. Short stroking quickens the shot cycle by reducing the amount of air available to be compressed (at the expense of increased preload needed to make power back up, possibly increasing the harshness of the shot cycle).
Piston sleeves. Another way of reducing noise, often used to calm a badly fitted spring.
Over lubing. Slap it all over, and boy can it feel smooth. It will shake off, migrate to the compression chamber and start shagging the seal all over again, so back to point 1.

The factory swept volume. Not ideal, but no disaster by any means.

The factory plank. Slack rake of pistol grip compromises any kind of decent trigger control, from what is a very good trigger.
Crap comb height for scope use, just about tops the lot off.

So in summary, out of the box, you end up with a harsh, boingy item, thats ergonoically poor.

But its all sortable

https://flic.kr/p/2kvQ8Hk

[robs5230]

So now we've established that an out of the box is a bit flawed, what can we do about it?

Just peg on with it is one option.
The shot cycle will calm down a tad, when all the factory lube has burned off, and you'll learn to live with it if you shoot it enough.
Choose the right pellet. I hear lots of stuff about finding the right pellet for the barrel. I don't really accept that. I think if you're going to shoot an out of the box rifle, you need to find the right pellet for the shot cycle.
Differing pellet brands and types, will all make the shot cyle different. Getting the right balance of resistance for the piston, will certainly improve the shot cycle and accuracy.

Starting to think about sorting the rifle, properly, is my option.
Trigger control. I have normal sized hands and fingers. If I were to use a factory stock, I'd fit a set back trigger blade. You'll never have good accuracy with poor trigger control.

The stock. Ergonomically, I don't get on with the factory stock. A CS500 sorts that.

The action. I've not shot an out of the box springer in over 25 years, probably more.
A basic strip clean and deburr is number one.
A new seal. I'd always chuck the one that came fitted. Check the fit of the seal you wish to use. Some factory seals can have an ok fit, some dont. Too loose, its no good, too tight, it needs sizing. There are after market options. Some good, some not so good, but the priority is fit.

Choose a spring. In a 95 I'd start with a 97 export spring of 3.1mm wire. Dehorn the closed ends of the spring. Stick your finger in each end of the spring and spin the spring on your finger. Wash the blood off, apply plaster, and get the file out.
Get guides made for the spring. Fit needs to snug but not too tight.
Ensure you have a power washer, for behind the top hat and between the spring and the base of the guide.

Choose a pellet you want to use. Say what ??? Yep, choose the pellet you want to use. They're pretty good barrels, and will shoot most pellets well (when set up right).
I shoot for pest control and prefer a light pellet so I always tune specifically for JSB express. I don't go by the batch theory either. Mine shoot any batch, any tin, straight out of the tin.

Assemble and check power.
I use moly sparingly. Just on the guide, top hat and spacers, the rest running dry. Apart from the cocking shoe that is.

I tune for express, so its easy for me. I aim for a power figure thats safe with express and lighter pellets, so 10.5 for me with express.
Start cutting the spring and refinishing bit by bit, until power drips where you want it, then make it back up with a spacer.
Its now optimised for the pellet.
I dont compress any coils other than the ends, and prefer all the spring length to be active.

I've found when I do it this way, all other common pellets, are way less efficient.

This works for me.
My 95's don't flip, boing, jump, dance or anything else.
They shoot asas well from a bag (hand rested or not) as they do freehand

[TopDog]

Spot on!! As a little exercise some while ago I did some recoil tests with my Test 80, light hold, firm hold, butt held firmly against cabinet (semi-rigid) and butt held firmly against wall (rigid). Will dig those out and post a collage of the results overlaid!

Action liveliness is of no real consequence as long as it, and the rifle/shooter interface, is the same every time. That, I think, is the essence of a springer and why they are so much fun to shoot! I always turn to springers for pleasure, the PCPs are for the clinical work!

atvb
David

Here's the hold sensitivity file I promised. I chose the results for the BrumBow since it is the medium weight barrel cocker which displaced the HW95 as my favourite and had not done the HW95.

http://freepdfhosting.com/d09abfdb29.pdf

Happy airgunning!
atvb
David

[TonyL]

Brilliant graphs, David. Thank you for sharing..