Taming a HW 80K

[Robert_Lavin]

Evening all,

Today has been a satisfactory day or airgun fettling.

The recently acquired .22 '80 has had a strip, clean and relube and seems to be shooting accurately. However, I've got a couple of problems:

1) It's a bit of a handful and is not the smoothest thing to operate or shoot so I think it needs a bit of refinement which leads to problem 2...

2) The Combro tells me that its muzzle energy is high 11s (FTTs) and I'm concerned that if I do any fettling or refining it'll be pushed over. I'm aware of the '80s reputation for being hard to keep legal so what might be the best option? Collapse the spring a bit? Chop the spring? Part or full drop-in kit? Substitute for delrin where I can? Just take the washer off the trigger end of the spring? Fill with grease to slow everything down? Just get FAC to negate the issue?

I don't want to spend a tonne of cash on it and pimp it completely though, I'm happy to keep it as true to what it is as possible.

Internals all look original to me. No evidence of dieseling at the moment.

Thanks,

Rob.

[dayglowfroggy]

Colapse one coil if its power your worried about but if you want it to shoot that bit nicer get the tbt drop in kit and the short stroke piston nose .

[CapitalBee]

Simplest mod' I found to improve the manners of my hw80 was add a short stroke nose extension to the piston. I got mine from Tinbum Tuning and It softened the shot cycle without increasing power (it stayed the same as before the mod')

[Robert_Lavin]

Colapse one coil if its power your worried about but if you want it to shoot that bit nicer get the tbt drop in kit and the short stroke piston nose .

For now, power is the main thing I'm worried about.

Manners can wait.

Is one coil enough? One end of the spring has a fairly flat finish, the other looks like it was cut half way around the spiral and is still stretched. I'll start by collapsing this flat to see if it has much effect.

Thanks.

[TonyL]

For now, power is the main thing I'm worried about.

Manners can wait.

Is one coil enough? One end of the spring has a fairly flat finish, the other looks like it was cut half way around the spiral and is still stretched. I'll start by collapsing this flat to see if it has much effect.

Thanks.

Sorting the cropped spring will most certainly help.

Also, I second and third the advice given above re fitting a short stroke extension nose. Cheap and very effective from you know who!

I've had the good fortune of shooting a few 'stroked 80s and they're lovely. By reducing the swept volume, it will also decrease the gun's propensity for trying to make too much power.

[Rickenbacker]

Yep, you'll need to finish that chopped end of the spring nicely Robert, which will drop the power a bit.

My thread here might be of interest to you for spring lengths etc: http://www.airgunbbs.com/showthread....=tuning+spring

But as said, Tinbum's piston nose extension is a great mod' on an '80.

[Jonjon79]

I've played with the innards of a couple of springers now but, not yet an 80.

I bought a used .177 97 that felt like a punch in the face each time I fired it.
When a friend opened up it up for me, there was a steel washer in there - swapping it for a delrin washer, and giving everything a good clean, polish and relube, really improved it.

It has risen to 848fps with FAPs and, is nice to use. I keep an eye on it with a chrono but, it hasn't increased any further for a while.
...... if your 80 was mine, I'd probably do exactly the same, and consider collapsing a coil or 2 later if needed.

Good luck with it

[Robert_Lavin]

Yep, you'll need to finish that chopped end of the spring nicely Robert, which will drop the power a bit.

My thread here might be of interest to you for spring lengths etc: http://www.airgunbbs.com/showthread....=tuning+spring

But as said, Tinbum's piston nose extension is a great mod' on an '80.

That spring length experiment was useful, I was looking for something that would give me an idea of the effect.

Thanks.

[TonyL]

My thread here might be of interest to you for spring lengths etc: http://www.airgunbbs.com/showthread....=tuning+spring

:

Just had a quick scan through that thread of yours, young Phil.

Awesome!

Most informative and a further example of how much superb information is contained amongst these hallowed pages.

And I can now reveal where I went on that most awesome road trip last February.









I went to see ----- ---- and --- -----.

Fantastic it was, too!

[Rickenbacker]

Steve Pope & God Almighty!?

[Robert_Lavin]

So, the supplementary question (before I go collapsing the spring) is how many pellets after a re-lube does it take for the muzzle velocity to stabilise?

Thanks.

[Rickenbacker]

If you don't get ANY wet lube forward of the piston seal - somewhere between 1 - 2 pellets should do it.

[Robert_Lavin]

If you don't get ANY wet lube forward of the piston seal - somewhere between 1 - 2 pellets should do it.

I'll be collapsing that spring then...

[TonyL]

Steve Pope & God Almighty!?

1) Correct.

2) Close.