Why is the HW95 so bouncy??

[evert]

Decided to take the .177" 95 out, since its been a couple months since I shot it the last time.
As we dont have power restrictions over here, this rifle is set up with a full power ARH/Maccari Hornet spring.
These have some closed coils at one end, giving added piston weight.
The spring is running on my own tight fit delrin/acetal/POM rear guide and tophat, and has thin steel washers behind the spring and in front of the tophat.
The seal is a ARH/Maccari SGS seal, which has shown itself to soften up sharp recoil without reducing power.
With this setup, 7.9 JSB Express are at 885fps and 8.2 RWS Meisterkugeln are at 910fps, indicating that the extra weight gives power to pellets with thicker skirts. Definately a FAC setup for you guys in the UK.

The gun recoils quite flat, and it is possible for me to shoot groups that are better than most other powerful springers I own.
It is more lively than a HW99/50s or a HW77/97 running at 10-11fpe, but it is really not very bouncy or unpleasant to fire.
The recoil is not extremely fast, but not very slow either.
I have tried the spring "backwards", without the added mass of the closed coils at the moving piston end of the spring, and this gave similar power but a very sharp snappy recoil, indicating that some extra piston weight is needed to stop bounce at this power level.

Anyway, to me, what experimentation with the 95 has shown me is that the gun has potential to be accurate.
But I have come to accept that it is made for power, and that it will never have the low recoil and be as easy to shoot as a gun that has its stroke/bore specifically designed for 10-11fpe.

[TonyL]

At the risk of sounding like a stuck record, I'm perfectly happy with the manners and accuracy of my 95s. Although not as "fast" as evert's due to UK compliancy, my early .177 muzzle weight version with V-Mach kit shoots flat. Is it all in the handling? (And, therefore, possibly less forgiving in various different positions - don't know). Or maybe it's all down to the character of the spring fitted. And maybe, just maybe (as mentioned earlier), a heavier piston (especially thinking about the cross sectional density) might just be helpful, too? Thinking steel top hat / weights.

I can fully understand Mr Geezer's comments and the 95 seems to be a rifle that has a lot of people chasing their tails, but I love it to bits and believe it to be one of the very finest springers out there. Both of mine are most certainly keepers.

[Hsing-ee]

The HW95 at sub 12 fpe is awful and HW should have made the HW50/99 to a higher engineering standard for the UK. So we're stuck with the pair of ladders bouncing around like a bowling ball on a see-saw with tuners great and small trying to make the thing shootable when it ought to be straight out of the box, its not like its some Chinese hopeful for a few quid, its an expensive top of the line job.

If you want a HW95 that works, get an HW98 or better still an HW77.

[averageplinker]

Ok, thinking out loud here......no experience of tuning either the HW99/50 or the HW85/95.

But I do have an HW50S and a MK1 HW85 ready to enjoy and improve. The received wisdom is that the 50S in .22" should be easy to get lovely and this thread indicates the 85 will be much more tricky.

I think they both run a 26mm piston but the 85/95 has a longer stroke so short stroking it to the same as a 50/99 is the answer is it not?? This thread suggests it is not that simple. So from a basic understanding of what goes into a springers dynamics there must be differences in piston weight, transfer port etc

Is there much difference between them and can the 85/85 be turned into a sweet shooting 50/99 clone but with a longer cylinder???

Rich.

[evert]

I think they both run a 26mm piston but the 85/95 has a longer stroke so short stroking it to the same as a 50/99 is the answer is it not??

I'm thinking to try something in between. The 99/50 is a bit too snappy for me when pushed above 10fpe.

[TonyL]

I'm thinking to try something in between. The 99/50 is a bit too snappy for me when pushed above 10fpe.

Whereas I really like them. As well as my own, I've tried a few other .177s at 10.5 or a smidge over and thought them to be very, very nice. And the first 99 I bought, a second hand. 22, was producing a very demure feeling.......13.5ft.lbs! I fitted a Wonkydonky kit and it now runs at an unbelievably sweet 11.25.. Amazing little things.

[averageplinker]

Sorry Tony somehow I missed your earlier post.

It's funny how the longer barrel of the HW85 is not favoured yet on the "trendy" carbine everyone wants more weight at the muzzle! I am hoping my "uncool" long .22" barrel makes my one shoot sweeter.

Rich.

[evert]

Whereas I really like them. As well as my own, I've tried a few other .177s at 10.5 or a smidge over and thought them to be very, very nice. And the first 99 I bought, a second hand. 22, was producing a very demure feeling.......13.5ft.lbs! I fitted a Wonkydonky kit and it now runs at an unbelievably sweet 11.25.. Amazing little things.

I wasn't smart enough to get myself a .22 HW99/50 before they were restricted over here, so I'm limited to .177".
Mine came new from the factory, giving a whopping 14fpe out of the box
The seal was damaged at the factory, and the action was full of grease, so it was dieseling heavily.
Anyhow, I've tried pushing it up and down in power, with several types of seals and different piston weights.
I've landed on a compromise, with 10.5fpe and a delrin tophat, which is quite good, but still a bit snappier than I prefer.
The action is probably perfect for a .22, but I'd like a few more mm's of stroke for the .177"

[Shed tuner]

I'm thinking to try something in between. The 99/50 is a bit too snappy for me when pushed above 10fpe.

exactly my experience too. I short stroked my 95 with a tbt nose, and it came out about 3mm longer stroke than the 99/50. Perfect for 12 FP

Details on this old thread:
http://www.airgunbbs.com/showthread....-on-an-HW85-95

[maximus]

Well, I've spent all afternoon buggering about with mine again! Tried every jsb variant i have, which is a lot, and the best accuracy was with the 7.9 but this was not all that I had hoped for. So onto the other brands, first up ftt, power dropped from 11 to 10.6 probably dueto how tight they were in the breech which caused bounce and made it twang like a good 'un. Accuracy was great though which was a bit heartening. Next up rws superfield, again great Accuracy power 10.7. I decided then to add 3 steel washers into the piston to hopefully counteract the bounce and kill the twang. This pushed the power up to 11.1with ftt and did mute the buzz but whilst still accurate not quite as good and ruined the accuracy with the superfield. It was doing 11.6 with FAP, so still legal. Now I have decided to try another spring which has about 50-60 mm preload. Can't chrono now as its gone dark but had a few shots to see how it shot. Big spring twang on a std hw guide which is a tightish fit so ill chrono tomorrow and see how i go. I may just go back to the set up that shot the superfield well, clean the barrel and give it a good try.