HW35 What have i bought

[Graemevw]

Its apart.
The spring guide has a star shaped end!
No washers to let the spring rotate.
Piston seal looks like new! Seems soft too, if a little tight in the cylinder. Looks like quite alot of lost volume in the center though.
Very sticky grease inside so ill seal breech, clean it all up and reassemble.

There was very little preload though, spring is 21cm long and a little bent, maybe time for a new one ill see if i can find out how long it should be.
Transfer port is 3mm by the way, in case anyones interested.

[mrto]

Its apart.
The spring guide has a star shaped end!
No washers to let the spring rotate.
Piston seal looks like new! Seems soft too, if a little tight in the cylinder. Looks like quite alot of lost volume in the center though.
Very sticky grease inside so ill seal breech, clean it all up and reassemble.

There was very little preload though, spring is 21cm long and a little bent, maybe time for a new one ill see if i can find out how long it should be.
Transfer port is 3mm by the way, in case anyones interested.

Your low power will probably be because of the tightness of the piston seal in the cylinder I have had this before with HW35's of this vintage and earlier.

If the spring is bent you will need a new one for the sake of a smooth shot cycle at least and if bent and knackered this will affect power too.

A clean up as you say with new spring, re-sized seal and new breech seal,(synthetic HW35 breech seals, http://www.airgunspares.com/store/pr...5-Breech-Seal/ will fit and are better than the leather original) will have your gun shooting quite nicely I would imagine.

These are available,by the way to convert the HW35 piston from leather to synthetic if you wish http://www.airgunspares.com/store/pr...-Head-Adaptor/ ,but leather seals shoot smoother in the 35's IMO.

ATB.

[I. J.]

These are available,by the way to convert the HW35 piston from leather to synthetic if you wish http://www.airgunspares.com/store/pr...-Head-Adaptor/ ,but leather seals shoot smoother in the 35's IMO.

ATB.

I agree that the leather washer shoot better than the nylon onesbut perhaps this has something to do with the transfer port being designed for each. http://smg.photobucket.com/user/Airs...tml?sort=6&o=2

[T 20]

Transfer port is 3mm by the way, in case anyones interested.

That port size will work with a synthetic seal if you do decide to use an adaptor.


All the best Mick

[Graemevw]

I think this 35 needs a new seal. Ive cleaned it all inside, oiled the leather seal, fitted a piston liner, stripped cleaned and polished the trigger and reasembled without grease. Ive done the leaky breach thing, fitted a new breach seal and a front sight.
its only doing 5.2 though. Piston seams to seal well and spring cant be too bad as its hard to get end block on.

Im pretty happy with just over 5 as id use it for bell target. Its quite consistant. Hardly any recoil, shoots nice, but im lucky to get half inch groups at 6 yards with open sights. Rekord triggers arent as great as I remember either.

Pick up my mercury again after the 35 and it handles better, trigger feels great (its set SUPER light) and its far more accurate despite a little bit of sharp recoil.

So im unsure if the 35 just isnt for me or if it will impress me more once the seal is sorted.
Which brings me to the question of seals, leather or synthetic. I know people say keep them leather but dieseling is a pain in the ass. It has 3mm port so ok for synthetic. Any difference in stroke etc between converter head and a later piston?

[CapitalBee]

With one of the adaptors fitted on the existing piston it will short stroke it slightly, as I seem to recall when I fitted a synthetic on one of my old leather sealed pistons. Can't say by how much, as I didn't measure it, but not a great deal.

[T 20]

With one of the adaptors fitted on the existing piston it will short stroke it slightly, as I seem to recall when I fitted a synthetic on one of my old leather sealed pistons. Can't say by how much, as I didn't measure it, but not a great deal.

About 3mm IIRC --- I'll measure one today to make sure.



All the best Mick

[Graemevw]

Would it be better then to get late piston instead? I guess in 177 it needs all the stroke it can get.

[T 20]

Would it be better then to get late piston instead? I guess in 177 it needs all the stroke it can get.

I like the early piston Graham, you can machine the front end back a bit keeping the 8mm stub then fit a synthetic seal adaptor so gaining up to 6mm extra stroke.

Now 6mm may not sound like much but it puts the stroke at 71mm which I find makes them really nice to shoot, which is what it's all about.



All the best Mick

[Graemevw]

Sounds good.
Not 100% sure ill keep it or not, ill shoulder it more and see if i can get comfortable with it. If i can, ill get the piston shortened, skim the back end down for buttoning and convert to synthetic.