Hw77 K help /advice

[ggggr]

I've been asked about an HW77 K someone has bought and have been asked to ask for a bit of advice on here.
It's serial number is 1007557 So which Mk is it? Is it also a 25mm piston seal? Can you get to the breech seal to change it easily? Can you strip the gun fully without a spring compressor?
AND ---this is the important bit -----It is missing the lock up set up on the cocking arm. What set up should this be? Is it different for different Mks?
Would I be right in thinking there is a plunger and a spring in the housing on the barrel rather than on the cocking arm?
Sorry for all the questions but totally new to me and something I wouldn't have an interest in myself.
Thanks

[Geezer]

Should be 25mm if original.

By the “lock up set up”, do you mean the catch for the locking lever? If so, yes there are at least three different versions over time. If you mean the ABT, it was common back in the day to remove it.

[Geezer]

My pleasure. Handy thread:

http://www.airgunbbs.com/showthread....he-under-lever

[Phil Russell]

Hi Guy ...Can you strip the gun without a compressor? Maybe ...It all depends on the spring as some can have quite a preload while others very little. But there is a way ...
Remove trigger unit (2 pins, watch out for the safety catch/spring leaping free. End block unscrews. If I do not know preload I will often get the end block turning then secure either the end block or the action in a padded vice while I unscrew the end block wearing leather gloves. There is about 20mm of thread. If there is a lot of preload then this method allows good control at the moment of release.
Good luck, Cheers, Phil

[gingernut]

Made in 1984.

[deejayuu]

Guy if it's confirmed Mk1 we have a simple fix for the catch and plenty of experience/info. on spring choice.
We watch with interest.

[Bedazzled]

I have a bear trap mechanism here doing nothing yours if you need it

[TonyL]

Thanks--I'll pass on the info.

I have been told via Pm the Mk1 has no lug bolt and the rear stock screw goes directly into the cylinder. SO sort or like my Op (I think) can you get the underlever plunger bits for this Mk?
Does anyone know a nice mainspring that will fit and not make it hot? Easy to compress-----little preload?

It's the front of the two screws in the trigger guard that goes directly into the stock. The rear (smaller one) goes into a captive nut at the rear of the trigger unit.

Yes, no lug. On the later ones, the "ABT" locates into this. But, personally, I remove it on the later guns anyway, allowing the facility to decock.

If you don't manage to sort the underlever catch, occasionally used units become available.

V-Mach springs have just about no preload with the end block removed, so really easy to fit. Always prudent to power check, though.

[StellaArtois Sr]

Personally I have worked on all of the Weihrauch models and not had to use a spring compressor on any of them.
Ade

[Phil Russell]

Personally I have worked on all of the Weihrauch models and not had to use a spring compressor on any of them.
Ade

I do not doubt you but if the history of the rifle in not known then I advise caution even if it only extends to securing the rifle firmly while you undo the action from the block or the block from the action with gloves (pref leather) on. An aftermarket strong spring (esp. Titan unless shortened) can give quite a wallop as the threads release so it is best to be prepared.
Cheers, Phil

[Geezer]

Ok--I got a look at the action of the gun today. It has 2 holes in the trigger block so it should be a Mk1.
It has a silencer thing at the front and a tube screwed to that by 3 grub screws. There is no foresight at all. The interesting thing is that the tube has a brass bush in it , which I am assuming should hold a spring and a ball. It was not popped over though and there was no bal or spring.
Is this off another model and been fitted to try to cure the problem or something else
Oh and the stock seem quite nice and has a cheek piece.
Thanks

Sounds like a contemporary noise suppressor. They were a common upgrade back in the day.

[T 20]

Thanks
The anti bear trap seem to have been removed. Yes I mean the cocking lever. I guessed at a spring and punger in the housing on the barrel with a screw to stop the plunger coming out/
Thanks

MK1 77s weren't fitted with an antibeartrap, Guy, and to fit one you'll need the antibeartap, lug, spacer, 6mm rear stock bolt and a MK2/3 77 stock.

IIRC, Jim made the sprung plunger for his old 77 by machining a bolt head down to act as a plunger/bearing and retaining the bolt in the housing with a nut at the muzzle.



All the best Mick

PS:- I'll return your call in the morning.

[billsnibby]

Hi,

I used a 5/16" cabinet ball catch to repair mine, packed out to the correct height to engage with the detent in the lever.
I think I had the idea from a thread on here somewhere.

HTH
Bill.

[billsnibby]

Here you go...

https://www./itm/Ball-Catch-Brass-8m...oAAOSw4shX3EJk

Alternatively if the link doesn't work search e6ay for 5/16" ball catch.

Best Regards,
Bill.