Help stripping and sorting a HW35k

[evert]

Neil, am I right in thinking that having carefully drifted out those two pins the end section of the action unscrews ? If it does I’ll see if I can rig up something using a large sash clamp, suitably padded of course

Norm

You can actually remove the rear block without removing the trigger, if you cock the trigger first.
The trigger must be cocked without cocking the mechanism, if that makes any sense. It is done by pushing p on the sear in front of the trigger housing. When this is done, just unscrew the rear block, and be careful with the preload the spring may be under.

[I. J.]

CAUTION The slot were the trigger unit fits can have razor sharp edges. A few mins dressing them down saves the digits. I also make sure the trigger retaining pins slide back nicely.

[Mr.Fixit-Norm]

CAUTION The slot were the trigger unit fits can have razor sharp edges. A few mins dressing them down saves the digits. I also make sure the trigger retaining pins slide back nicely.

Cheers I.J. That trigger slot is certainly sharp ! I carefully took an old car points file to the edges and it’s no longer a finger slicer

[TonyL]

That transfer port sounds mahoosive and will need sleeving down to (circa) 3.2 to 3.4mm?

Spring and guide kits? Tinbum, Welsh Willy or a V-Mach one from Lyn Lewington if he has any remaining? And I'd be replacing the piston and breech seals (which you had already mentioned) and the barrel shims for good measure.

[Shed tuner]

That transfer port sounds mahoosive and will need sleeving down to (circa) 3.2 to 3.4mm?

yup. I saw the huge TP marks on the end of the piston seal too - it's obviously slamming. Looks like 5mm - crazy.

It's long, so defo sleave it down to 3mm ish or it's always going to shoot horribly and with low power. Explains the recoil and harsh cycle too.

[TonyL]

Maybe also worth changing the barrel latch spring?

I wonder if those horizontal markings in the "wear groove" from the barrel latch on the cylinder end occurred due to striction in the latch? Good idea to clean that latch recess and lube. Not sure if that wear groove can be tidied a little somehow? I've never had to do it. Guessing one of our engineers will have......

[u.k.neil]

Did you all notice that the spring that came out had been chopped at one end and then left "as is" with no flattening and grinding square?



Neil

[uiooloa]

Who can tell me if I can buy some piston here if I am from Canada, see here. Is that possible at all? I think I will have to go to the US? But will I than be able to go through the border? It looks like I will be able to get such goods only at home. If you know more in this respect, please inform me. I will try to look for more information on the internet.

[Mr.Fixit-Norm]

Maybe also worth changing the barrel latch spring?

I wonder if those horizontal markings in the "wear groove" from the barrel latch on the cylinder end occurred due to striction in the latch? Good idea to clean that latch recess and lube. Not sure if that wear groove can be tidied a little somehow? I've never had to do it. Guessing one of our engineers will have......

That transfer port sounds mahoosive and will need sleeving down to (circa) 3.2 to 3.4mm?

Spring and guide kits? Tinbum, Welsh Willy or a V-Mach one from Lyn Lewington if he has any remaining? And I'd be replacing the piston and breech seals (which you had already mentioned) and the barrel shims for good measure.

Hi Tony,
I’ve ordered up a tin bum maxi kit for it and I’ll change the breech seal as well I may need to cut down or compress the spring from the kit but that won’t be an issue.

It’s odd that the transfer port is so big, I measured it with callipers initially then found a 5mm drill and gently put the blunt end in, it goes in but not all the way through, does this mean the inside cylinder end is smaller

yup. I saw the huge TP marks on the end of the piston seal too - it's obviously slamming. Looks like 5mm - crazy.

It's long, so defo sleave it down to 3mm ish or it's always going to shoot horribly and with low power. Explains the recoil and harsh cycle too.

It’s certainly had recoil and needed a lot of effort to cock it, I did fire it when I picked it up and at about 10yrds into the side grain of a split piece of dried kindling log. The pellets were burying themselves right in so it certainly didn’t feel down on power !
I could’ve kicked myself for not running it over my combro now before I dismantled it

Looks like I’ve got a bit more work to do. It’s my first Weihrauch ( actually spelt it right there, you guys are obviously too polite to correct me ), and I was impressed with the build quality !

It’s my birthday today so fettling will cease until tomorrow as my sons coming over lunchtime and we’re round my daughters for a takeaway tonight

Thanks for all the help.

Norm

[T 20]

Hi Tony,
I’ve ordered up a tin bum maxi kit for it and I’ll change the breech seal as well I may need to cut down or compress the spring from the kit but that won’t be an issue.

It’s odd that the transfer port is so big, I measured it with callipers initially then found a 5mm drill and gently put the blunt end in, it goes in but not all the way through, does this mean the inside cylinder end is smaller



It’s certainly had recoil and needed a lot of effort to cock it, I did fire it when I picked it up and at about 10yrds into the side grain of a split piece of dried kindling log. The pellets were burying themselves right in so it certainly didn’t feel down on power !
I could’ve kicked myself for not running it over my combro now before I dismantled it

Looks like I’ve got a bit more work to do. It’s my first Weihrauch ( actually spelt it right there, you guys are obviously too polite to correct me ), and I was impressed with the build quality !

It’s my birthday today so fettling will cease until tomorrow as my sons coming over lunchtime and we’re round my daughters for a takeaway tonight

Thanks for all the help.

Norm

Happy Birthday Norm.

The first thing I'd do is stick it back together and run a chrono string.
Then I'd sleeve the transfer port down to 3mm and run a second chrono string, then I'd be looking at fitting a tuning kit.

The cut down OX Spring is not to everyone's taste but whoever tried to tune it was heading in the right direction by cutting it down.
I have a HW35 that I was given in 1986 and even though I've changed almost every other part of the gun it still has the same OX Spring in it that it came with.
The only preload on this OX Spring is created by screwing the trigger block into the cylinder.





All the best Mick