HW35 With Rotating Piston

[T 20]

So after blacking I've polished out the cylinder, sized an old Knibbs red seal, slightly altered the latch and rebuilt her.
The only Spring I had to hand was a well used old school HW50 Spring which fitted perfectly.

With a 13"" 0.22" barrel I'm getting this :-

Superdome averaging 590 feet per second.

Hobby averaging 670 feet per second.

[joffy]

So after blacking I've polished out the cylinder, sized an old Knibbs red seal, slightly altered the latch and rebuilt her.
The only Spring I had to hand was a well used old school HW50 Spring which fitted perfectly.

With a 13"" 0.22" barrel I'm getting this :-

Superdome averaging 590 feet per second.

Hobby averaging 670 feet per second.

Sounds like a result

[Shed tuner]

try it with FAPs... sounds like it dislikes large/tight pellets, and likes light ones.

FAP might make it quite warm (and shoot very nicely too)

[TonyL]

A result indeed.

As JB says, certainly worth a go with the Falcons / JSB RS. Although my recently de-tuned Supersport did actually make a little more power with the Hobbies despite them being a very tight fit.

A little scooe for de-tuning slightly and making it even sweeter?

[T 20]

try it with FAPs... sounds like it dislikes large/tight pellets, and likes light ones.

FAP might make it quite warm (and shoot very nicely too)

I'll get back into it in the morning, Jon, I had to abandon it this afternoon as a rush job came in.

I still have a few tidy up jobs to do on the gun, I designed the piston to have 2mm clearance with the cocking arm, the Knibbs seal I used turned out to be 1mm shorter than a Weihrauch seal so cutting the clearance down to 1mm --- a quick file of the cocking arm will sort that, or I'll just get a new genuine seal.

The barrel looks like it could do with checking for straight and given a quick tweak, it's also crying out for a barrel weight come cocking aid, so while I have the .22" barrel off I may as well fit my spare .177" K barrel and run a chrono string with that.

So far so good though.

[Bluefan]

Top work Mick Just too long till we all get to ogle/slobber all over it

[TonyL]

Top work Mick Just too long till we all get to ogle/slobber all over it

24 sleeps until Boxing Day, Gav.

[Bluefan]

24 sleeps until Boxing Day, Gav.

Oh yea I'd forgotten that sooner than I thought

[T 20]

Top work Mick Just too long till we all get to ogle/slobber all over it

It just looks like every other 35k, Gav, but it's lazerglided and long stroked.

I suppose you'll want a caggie handed stock on it ?

[Bluefan]

It just looks like every other 35k, Gav, but it's lazerglided and long stroked.

I suppose you'll want a caggie handed stock on it ?

Well it might look like every other 35k but we know it isn't If you should happen to have a stock resembling that description then I wouldn't say no if you fitted it There are very few examples left in the wild up North most have been herded into IJ's coral.
Iwas actually thinking of the rust blued finish you have been working on .

[TonyL]

It just looks like every other 35k, Gav, but it's lazerglided and long stroked.
:

A bit like your B2 looks (just) a little like any other B2 eh, Mick.

[T 20]

I still have a few tidy up jobs to do on the gun, I designed the piston to have 2mm clearance with the cocking arm, the Knibbs seal I used turned out to be 1mm shorter than a Weihrauch seal so cutting the clearance down to 1mm --- a quick file of the cocking arm will sort that, or I'll just get a new genuine seal.

Well it turned out that the Knibbs piston seal was moving fore and aft on the piston by .75mm so by simply cutting a circular piece of 1mm gasket paper and fitting it into the piston seal before fitting to the piston put me back to the designed 2mm clearance.

So all I ended up doing to the cocking arm was to polish the foot which fits inside the cylinder.

The barrel looks like it could do with checking for straight and given a quick tweak, it's also crying out for a barrel weight come cocking aid, so while I have the .22" barrel off I may as well fit my spare .177" K barrel and run a chrono string with that.

Yep, the barrel was bent, but it isn't now but while I was refitting it I noticed the barrel latch was a little bit stiff and wasn't engaging correctly so I polished the three unseen sides of it until it worked as it should do.

I also polished the spring ends and lubed the gun before reassembly, as the chrono test yesterday was run with the gun dry except for a smear of silicon oil on the piston seal.

Following another chrono session the gun is now locked in the naughty cupboard with a copy of the 1968 firearms act reflecting on the day's events --- I'll definitely be coil squashing in the morning.

[pigeondave]

So all I ended up doing to the cocking arm was to polish the foot which fits inside the cylinder.

Have you done this because its a rotating piston or should this be done as a matter of course, when the rifle is in bits?

Which bits did you polish? Any chance of a pic with arrows please.

[TonyL]

Nice one, Mick.

I hope you get the tinkering time today to free it from the naughty step

Pigeondave....always a good idea to them.