HW77 Strip and Clean

[Robert_Lavin]

Afternoon,

My (new to me) HW77K (25mm) needs a bit of TLC.

The saftey catch pin / button had no spring. I believe it should. Does it matter if it hasn't?

Are the front stock washers anything special or should I be able to pick them up from a hardware store?

The piston seal is very dark. I presume this is evidence of dieselling in the past. Is it worth changing? Power was fine before I took it apart; I don't know about after yet since it's still in bits!

It's also got a mega twang on it which I'm hoping to quieten down. Any tips further than a clean and relube? I'm trying to sort it myself before I resort to a drop in kit.

Thanks,

Rob.

[Zomboid]

I've just done my 77. All I did was relube, add top hat and longer spring guide with a piston sleeve. Used the standard spring. It was very twangy before, but is more of thwack now.

Remember to get it chrono'd though.

And the only bit I got unstuck with was, when replacing the trigger unit, set it as "cocked" before putting back the retaining pins!

[peddy]

Afternoon,

My (new to me) HW77K (25mm) needs a bit of TLC.

The saftey catch pin / button had no spring. I believe it should. Does it matter if it hasn't?

Are the front stock washers anything special or should I be able to pick them up from a hardware store?

The piston seal is very dark. I presume this is evidence of dieselling in the past. Is it worth changing? Power was fine before I took it apart; I don't know about after yet since it's still in bits!

It's also got a mega twang on it which I'm hoping to quieten down. Any tips further than a clean and relube? I'm trying to sort it myself before I resort to a drop in kit.

Thanks,

Rob.

If you don't want to replace the spring in the safety catch I'd remove the catch all together rather than leave it in without one. I'd also replace the piston seal as it will be hardened with dieseling, as mentioned a decent Spring guide and I'd fit a ptfe sleeve in there aswell.

[Robert_Lavin]

If you don't want to replace the spring in the safety catch I'd remove the catch all together rather than leave it in without one.

Having put it back together, I now realise what the spring does and I'd like to have a fully working safety.

I'll be getting on to Chambers. I'll order a front stock washer whilst I'm at it.

Thanks,

Rob.

[tinbum]

Having put it back together, I now realise what the spring does and I'd like to have a fully working safety.

I'll be getting on to Chambers. I'll order a front stock washer whilst I'm at it.

Thanks,

Rob.

Retractable pen springs can be used at a push.

[Robert_Lavin]

Having just looked at the service kit from Chambers it appears that I don't have a Weihrauch spring in this rifle, it's a square section thing instead. Can anyone tell me anymore about these things? Specifically if it's making the rifle twangier than it ought.

Thanks again,

Rob.

[tinbum]

HW fitted square section springs as standard for a while. They changed back!
They can work well and there was one fitted in mk1 HW97 I have whch was ok. I changed it for a new HW one with fitted guides though.

[TonyL]

Having just looked at the service kit from Chambers it appears that I don't have a Weihrauch spring in this rifle, it's a square section thing instead. Can anyone tell me anymore about these things? Specifically if it's making the rifle twangier than it ought.

Thanks again,

Rob.

As Tinners says, they can actually be okay with the (factory) square section spring, but not with an Ox / Air Force etc.

However, I think this is good enough reason / excuse to go for a spring and guide set - either V-Mach or TbT. If you can't make the guide and top hat yourself, either of these will be a fine investment with the guides matched exactly to the spring. These are the main ingredients of shooting refinement in a springer, with the piston sleeve helping further still. Piston sleeve is an easy do-at-home addition.

[Robert_Lavin]

Thanks all.

I've got a service kit (inc. spring) winging it's way to me. I'll stick that in and then I expect I'll be after a guide and a top hat.

Regards,

Rob.

[Robert_Lavin]

As Tinners says, they can actually be okay with the (factory) square section spring, but not with an Ox / Air Force etc.

However, I think this is good enough reason / excuse to go for a spring and guide set - either V-Mach or TbT. If you can't make the guide and top hat yourself, either of these will be a fine investment with the guides matched exactly to the spring. These are the main ingredients of shooting refinement in a springer, with the piston sleeve helping further still. Piston sleeve is an easy do-at-home addition.

Just so I know, are their any distinguishing features for the factory, square section spring? I suppose the length is the obvious one, which I'll measure next time it comes apart, but is their anything else?

Thanks,

Rob.

[Robert_Lavin]

If anyone's still reading, the service kit has transformed the gun.

I doubt the spring that was in it was a square-section Weirhauch one; it was about an inch longer than the new one. It was also an absolute sod to get back in the gun, the new one wasn't to the extent that I was concerned that it might not have been a UK spec spring!

Thanks for all of your help.

Rob.

[webb22]

i'm still reading this mate .... i just picked up a full length (18.5" barrel) '77, s/n 1022***, so its an early one i gather? just missing a rear sight though, but can't complain, as it was a bargain IMO it shoots wonderfully, with regards to accuracy, but it also has a terrible twang the old boy said he had 'tuned' it (polished the internals and light grease), but I'm guessing it will need a sleeve, from what the chaps have said above? hopefully TbT et al will set me straight on this ...

[Robert_Lavin]

i'm still reading this mate .... i just picked up a full length (18.5" barrel) '77, s/n 1022***, so its an early one i gather? just missing a rear sight though, but can't complain, as it was a bargain IMO it shoots wonderfully, with regards to accuracy, but it also has a terrible twang the old boy said he had 'tuned' it (polished the internals and light grease), but I'm guessing it will need a sleeve, from what the chaps have said above? hopefully TbT et al will set me straight on this ...

Mine's s/n 1286*** and around 1993 (extrapolated) according to the online Weihrauch database.

I haven't bothered with a sleeve, I just wanted to get it back to something that I knew was close to "standard" internals and work from there. As it is now, it's quiet, the twang is gone and it groups tighter than when I acquired it without really thinking too hard about it.

I'll shoot it for a while and then decide whether I want to "add delrin", although having read another thread on here I'm beginning to think that the nasty, steel spring guide is too tight a fit so it might be sooner rather than later.

Rob.