HW95 problems

[Daveo]

Hi guys,
The HW springer bug has truly bitten
I’ve bought a little used .20 HW95 2022 dated.
Complete with TbT sticker,
Wasn’t that impressed with the shot cycle, it was a bit twangy 10.4 ftlb, accurate though!
so I dropped the stock although there is a drop in kit fitted it’s dry as a bone.
That’s when the fun started, I couldn’t slide the piston out.
It as though the piston seal is way too tight.
Finally persuaded the piston free, it’s a standard parachute seal.
There was crud in the lip of the seal, so I hoped that’s what was holding it up.
It’s not, I cleaned everything up
The piston apart from one witness mark is in good nick
Reassembled with moly couldn’t push the piston in easily, I had to tap it in with a nylon hammer!
I better in the actually comp tube, it does slide up and down.
So I put it back together
It gritty as hell upon cocking, I’ve not even bothered shooting it.
Has anyone seen a tight seal like this before?
Any suggestions?

Cheers Dave

[Dragonboy]

Never had any issues with the standard HW piston seals. Maybe worth replacing the seal? Or you could try resizing the seal first?

[Scrinja]

If i have any issue's like that while its stripped down i would'nt be putting it back together with a hammer bro
Resizing the seal when you hammer it out again seems like a good idea ..

[Neil54]

I would try a new piston seal.
They can go hard depending on what they have been in contact with.

[Bellycrawler]

I'd of replaced the seal before I re assembled. Possible that it's been worked on then some one has touched it with magic hands to improve it later.

[NickG]

If you hammered it in ,the cutouts in the action will have shredded the seal .

[maximus]

In my experience the new HW seals are usually on the loose side if anything. As said best to replace with a genuine new HW seal.

Regards Max

[Daveo]

I didn’t smash the granny out of it with a hammer! Just coaxed back into place trying to work out what was grabbing.
I stuck it back together thinking it was just a tight seal and in the next 150 years it might bed in
It’s been pissing me off all day at work so I’ve pulled it in bits again
It’s the piston itself, the piston skirt isn’t round, there is a millimetre difference in the skirt measured across and up and down
I can’t imagine how it’s got egg shaped unless someone’s held it in a vice,
Which is exactly what I’ve done with soft jaws to make it round again
It’s sliding freely now
Measuring about 25.7mm give or take all round now, the latch rod wasn’t true either so I’ve straightened that up
Weird!
Anyway I’ve ordered a new seal for it

[rapidresponse1]

hope you get it sorted bud

[tinbum]

If you have any issues when the seal arrives you can ring me on 0800 number. I know you didn’t buy the kit, but I can still probably help

[Daveo]

If you have any issues when the seal arrives you can ring me on 0800 number. I know you didn’t buy the kit, but I can still probably help

Thank you that’s damn decent of you.

[deejayuu]

I would insert piston/seal backwards to find tight spot on seal then remove material from that point on in small increments til suitable fit achieved.
Quite common occurrence here

[Travis299]

Hi guys,
The HW springer bug has truly bitten
I’ve bought a little used .20 HW95 2022 dated.
Complete with TbT sticker,
Wasn’t that impressed with the shot cycle, it was a bit twangy 10.4 ftlb, accurate though!
so I dropped the stock although there is a drop in kit fitted it’s dry as a bone.
That’s when the fun started, I couldn’t slide the piston out.
It as though the piston seal is way too tight.
Finally persuaded the piston free, it’s a standard parachute seal.
There was crud in the lip of the seal, so I hoped that’s what was holding it up.
It’s not, I cleaned everything up
The piston apart from one witness mark is in good nick
Reassembled with moly couldn’t push the piston in easily, I had to tap it in with a nylon hammer!
I better in the actually comp tube, it does slide up and down.
So I put it back together
It gritty as hell upon cocking, I’ve not even bothered shooting it.
Has anyone seen a tight seal like this before?
Any suggestions?

Cheers Dave

Pic of a Weihrauch factory seal. My rifle is absolutely silent cocking until the trigger latch & averages 17 FPE.

[Daveo]

Pic of a Weihrauch factory seal. My rifle is absolutely silent cocking until the trigger latch & averages 17 FPE.

Is that in a ‘95?

I would insert piston/seal backwards to find tight spot on seal then remove material from that point on in small increments til suitable fit achieved.
Quite common occurrence here

It’s not the seal, it was an oval piston skirt,
Hopefully it’ll go back together easily now thanks for the input.

hope you get it sorted bud

Cheers pal

[Shed tuner]

you've identified it now anyways, but when I get a tight piston/seal, I always remove the seal first and insert the bare piston, to check for clearance. It's not that rare to get either out of round pistons, or damage to compression cylinders. Yours sounds pretty extreme though. Piston seal arbours out of true with the piston itself are pretty common too.