A well sorted, sweet shooting HW35.
The '35 first came to my attention back in 1977 with the launch of Airgun World. And I think I got my first one the year after. Loved them ever since.
Apologies for the drawn out nature of the next bit, especially for people that may have read some of my previous ramblings on this particular gun. I bought the gun in question back in 2008 from an old acquaintance. When he offered me it he did say that it was "a bit rough"! I duly went and viewed and yes, it was most certainly a little cosmetically challenged. Rusty and the stock badly scrawked in places. The breech seal was a sticky, goo-ey mess. When I asked him about the seal he said, "Oh, my daughter probably stuck a fruit pastille in there". And it would seem he wasn't wrong!
When I asked him how much he wanted he said to make him an offer. I didn't want to as I didn't want to offend. He then said, "Oh, just give me £20". I thought that that was too cheap so we settled at £30,
Once I stripped it, the cylinder and piston were in perfect condition. The leather seal was goosed. I duly ordered a standard spring, breech seal and barrel shims from a shop. They had no leather seals but said that Knibbs may have some. I rang Knibbs who said they had the leather seals so I ordered one. Over the next couple of days the bits arrived........A Titan spring "oh, sorry, no standard ones" which had to be cut down and the seal from Knibbs.....well, not a seal but a synthetic head conversion plus red synthetic seal and a credit card receipt for a larger amount than expected.....naughty, naughty!
Anyways, cutting the very long story a little shorter, I eventually ended up with a V-Mach spring and guide kit and running the Knibbs synthetic set-up.
The gun shot beautifully. Very, very sweet and extremely accurate. The power was low at 7.5ft.lbs, but I decided that that was okay as I only intended using at short range at home on the open sights. At ten yards, if I do my bit, the gun will print pellet sized ten shot holes all day.
So a happy bunny I was.
Then, once I joined the BBS seven plus years ago I came across the leaky breech threads and Mick (T20's) excellent detailed information and also the helpful info from Bigtoe. I had it mind that I might have a go, one day.
Anyway, a few weeks ago, that lovely gentleman Mick donated a later type piston to the cause. Thank you, Mick. And this meant I simply had to do it.
I trawled the 'net for Loctite product but struggled to find the stuff I wanted. But then settled on JB Weld Perma-Lock from "The House of Glues". Product duly arrived. I also ordered up a standard HW piston and breech seal from Knibbs.
When I stripped the gun, the piston was INCREDIBLY tight. Oh yes, just remembered, I chrono'd the gun immediately before the strip.......4ft.lbs!
Must be the leaky breech, yes?
Anyway, I applied the Perma-Lock to the cylinder. Polished and moly treated the piston. The V-Mach spring and guide kit looked pristine so we re-used. Rebuilt last week but couldn't chrono due to lighting conditions for the F1. But I did have a plink down the hallway (it was lashing it down outside). Power output sounded healthier and the gun retains its previous superb firing manners and accuracy.
I finally managed to run some shots over the chrono yesterday........I was expecting a rise due to the breech "fix", a much nicer piston seal fit and the increased stroke......result.....an effortless 11ft.lbs and excellent consistency. And that seal still needs to run in!
So, very, very happy. In fact, I'm well made up.
So the spec?.......Standard TP (larger for the leather seal; this is a pre-safety model), piston from the later synthetic sealed guns - lighter and 4 or 5 mm more stroke, standard HW seal, V-Mach spring and guide kit. There's just about no static preload on it. The end of the guide sits a good few mm down the threads, so a good few turns required of the back block before it starts to apply any preload. This makes future strip downs even easier, of course. I also wonder if this also helps with the longevity of the spring?
I absolutely love this gun. It was always going to be a keeper; even more so now.
Cheers for reading.
P.S.....If I have any regrets it's this......If I had more spare time it would have been nice to assess the improvements in individual stages gained from the breech fix, the longer stroke and the much better fitting seal. As I have so little spare time, everything was combined in the one job. I can't remember that red Knibbs seal feeling that tight when I first built it, but it was horrendously tight when I stripped the gun. I wonder if the material isn't quite up to the job and it's been "hammered larger", almost like a PTFE seal with no memory? And maybe, if the breech was leaking, excessively hard piston landing exacerbated this? I strongly, strongly suspect that the huge rob in power may have been due to the horribly tight seal.
Reply With QuoteOriginally Posted by TonyL
A well sorted, sweet shooting HW35.
