HW 80 30mm ss

[wonky donky]

Just had a play with my .22 HW80, the one I short stroked to 68mm with rotating piston. Power was always going to be a problem at that stroke .22 so decided to reduce the stroke even more.

Piston weight 284grms, bit heavy, pre-load 60mm, transfer port 3.6mm std lth.

Now getting Superdomes @ 588fps 11.04fpe
H&N FTT @585fps 11.8fpe
AA DField @557fps 10.95fpe
Hobby @641fps 11.09fpe

Firing cycle nice, soft but quick, pre-load is a little high, Vo very consistant so inclined to leave as is.

Any advice chaps? Oh the stroke? 48mm

[TopDog]

Just had a play with my .22 HW80, the one I short stroked to 68mm with rotating piston. Power was always going to be a problem at that stroke .22 so decided to reduce the stroke even more.

Piston weight 284grms, bit heavy, pre-load 60mm, transfer port 3.6mm std lth.

Now getting Superdomes @ 588fps 11.04fpe
H&N FTT @585fps 11.8fpe
AA DField @557fps 10.95fpe
Hobby @641fps 11.09fpe

Firing cycle nice, soft but quick, pre-load is a little high, Vo very consistant so inclined to leave as is.

Any advice chaps? Oh the stroke? 48mm

This is interesting! What are the spring dimensions by the way (free length, coil count, wire diam, O/D)?

What sort of MV consistency over a 10 shot string do you get?

Keep up the research!

atvb
David

[vobster]

Just had a play with my .22 HW80, the one I short stroked to 68mm with rotating piston. Power was always going to be a problem at that stroke .22 so decided to reduce the stroke even more.

Piston weight 284grms, bit heavy, pre-load 60mm, transfer port 3.6mm std lth.

Now getting Superdomes @ 588fps 11.04fpe
H&N FTT @585fps 11.8fpe
AA DField @557fps 10.95fpe
Hobby @641fps 11.09fpe

Firing cycle nice, soft but quick, pre-load is a little high, Vo very consistant so inclined to leave as is.

Any advice chaps? Oh the stroke? 48mm

48 Love to have a go of that to see what it feels like. Hows the accuracy?

[Shed tuner]

Bring it to the bash please Dave

[flatrajectory]

Amazing.!!!!
P.p.

[wonky donky]

This is interesting! What are the spring dimensions by the way (free length, coil count, wire diam, O/D)?

What sort of MV consistency over a 10 shot string do you get?

Keep up the research!

atvb
David

David the spring is 3.25 wire....14 i/d.....f/l 248 Pe-load 62mm 34.5 coils closed & ground.

There is a 2mm thrust washer on the guide which itself fits into a 2.5mm recess in the trigger block.

The top hat has a 5mm base witha 10mm stem. the piston has some slip washers inside now bringing the weight up to 308 grams with the seal & top hat. I made the slight change to pre-load just to see if Vo responded as per normal or if it was beginning to become over sprung,...Not a bit of it!

Vo is now 595/600fps with H&N FTT .22 5.52mm

Consistency is very good 4/6 fps

I'm running the old type seal, I did try the new type with a huge loss in Vo cica 200fps.......I'm not surprised by this, well maybe a little but found the old seal to give better results in the 80.

If you need anything else give me a shout!

[wonky donky]

48 Love to have a go of that to see what it feels like. Hows the accuracy?

Come to the bash & shoot it, it would be my pleasure.

[wonky donky]

Bring it to the bash please Dave

Don't know if I can keep my hands off it that long Jon It's an old dog of a rifle now looking worse for wear. Yes I'll bring it of course, TonyL would never forgive me if I left it at home It shoots nicer at the 60mm stroke but this is definitely different!

[wonky donky]

Amazing.!!!!
P.p.

I might even let you try it Pete!

[vobster]

Come to the bash & shoot it, it would be my pleasure.

I'll see if I can make it

[TonyL]

Blimey!

Nice one, Mr Wonky!

That sounds awesome. Would love a go at the Bash if that's okay?

[bigtoe01]

48mm stroke...love it! I ran one of mine a few years back at 55mm stroke and it produced over 12 with ease

That has to have a seriously fast shot cycle...interesting about the seal, I have some Vortek (vac 30) seals and maccari (flat faced) seals here, if you want to try them just shout at me

[Lanky94]

What a brilliant idea.......setting the thrust washer into the trigger block to give more room.

What diameter is the piston itself Dave?

[bigtoe01]

What a brilliant idea.......setting the thrust washer into the trigger block to give more room.

What diameter is the piston itself Dave?

http://s202.photobucket.com/user/won...tml?sort=3&o=3

thats off Daves photobucket, its the piston in his 80

30mm seal,

[TopDog]

David the spring is 3.25 wire....14 i/d.....f/l 248 Pe-load 62mm

There is a 2mm thrust washer on the guide which itself fits into a 2.5mm recess in the trigger block.

The top hat has a 5mm base witha 10mm stem. the piston has some slip washers inside now bringing the weight up to 308 grams with the seal & top hat. I made the slight change to pre-load just to see if Vo responded as per normal or if it was beginning to become over sprung,...Not a bit of it!

Vo is now 595/600fps with H&N FTT .22 5.52mm

Consistency is very good 4/6 fps

I'm running the old type seal, I did try the new type with a huge loss in Vo cica 200fps.......I'm not surprised by this, well maybe a little but found the old seal to give better results in the 80.

If you need anything else give me a shout!

No' of coils is missing; can you advise please?

atvb
David