Is you piston seal synthetic? Spring for .177 should be 215/220 x 23 OD x 3.6 wire x 28 coil x 54 lb/inch rate
Right, rather than sit watching the box all evening I decided to head to the workshop and strip the 35 beastie
The main spring had quite a bit of preload, about 25mm and is indeed a square section one. Whether it’s an Ox one or not I don’t know ?
Following the TBT guide on the HW80 it didn’t take long to have it all in bits, rather than fudge up a spring compressor I settled for wrapping it in a big thick towel and unscrewing it, it wasn’t as bad as I thought either.
The breech end seems to have some slight wear on the top right hand side and the transfer port end had quite a bit of wear, presumably where the latch rubs ?
The good thing is it’s got the later type synthetic piston seal and the internals look in good condition. The piston is going to need a good clean and polish ( The TBT method looks good ), and I’ll give the cylinder a good degrease as well.
What I really need now from the good folks on here is advice on what spring to use ? I’m not after lots of power 10 - 10.5ftlbs would be plenty, my main concern is no or minimal twang and a smooth easy cocking effort.
I know I’ll need a new spring guide & top hat and I may as well fit a new piston seal and breech seal at the same time.
I’ve taken photos and loads of measurements if this would help in any ideas or suggestions.
This is what I’ve got so far.
Spring.
28.5 coils, square section approx 3.67mm, ID 15.72mm OD 23mm Length 217mm
Piston.
Length inc seal 122mm, Dia, seal end ~29.25mm, latch end ~ 29.7mm ( where the ‘wear’ is )
Barrel, 410mm, Transfer port 5mm
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.
Last edited by TonyL; 10-07-2021 at 06:08 AM. Reason: Seals.
THE BOINGER BASH AT QUIGLEY HOLLOW. MAKING GREAT MEMORIES SINCE 15th JUNE, 2013.
NEXT EVENT :- August 3/4, 2024.........BOING!!
Always looking for any cheap, interesting, knackered "project" guns. Thanks, JB.
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......
THE BOINGER BASH AT QUIGLEY HOLLOW. MAKING GREAT MEMORIES SINCE 15th JUNE, 2013.
NEXT EVENT :- August 3/4, 2024.........BOING!!