Diana 35 power dreams

[Shed tuner]

I am not familiar with the Vulcan air rifle barrel construction but I checked it now (with google) and it is very close to the project.
Here are a couple of pictures of the Gamo Hunter 1250 rifle from another site that shows the final outcome of such a piece of engineering.

http://24ars.ru/upload/iblock/1da/1d...7fe811dbd5.jpg

yup, exactly that. A lot of work though, and a milling machine. One can easily cross that line where you are making a new gun, and it's always cheaper to just buy what you need instead once you get to that point.

[jlb73]

It will be very interesting to compare Diana 35 and 34 vital statistics, has anyone do this?

[evert]

All that work for 8 fpe ... you can get that out of a HW30 without even trying in .22.

But what is the fun in that? Dont we all have at least one HW30 already?

IIRC the 35S does use a different piston, spring, or both. Though that may be to accommodate the articulated cocking link and ABT rather than to increase power.

The 35 is a nice rifle. I have two. I think this thread shows that trying to add 1ft-lb to their muzzle energy would require significant engineering. And why do it when you could just buy, say, a Diana 34 or one of many other rifles of similar size and weight but slightly higher power?

In my mind, the Diana 35 has a timeless classic look and feel, it is somewhat of an archetype of what I feel an air rifle should be, both in looks and apperance. Plus, a soft shooting 10fpe rifle is better than a slammy 8fpe rifle ;-)

[BTDT]

The main issue with the 35 is the short compression stroke. If the swept volume remained the same, but the bore was 25mm, the stroke would be 85mm, exactly the same as my and a few HFT competitors' rifles, which have no problem achieving satisfactory muzzle energy.

The length of the transfer port is not ideal, but it's not a huge issue - the LGV port is longer and the rifle easily achieves our legal limit and 15 ft. lb. in export markets. I agree it's too wide as it was set for a dieseling rifle, and ~3mm would be a better option.

One thing I don't think anyone has mentioned is the available space for the mainspring. If there isn't enough length for a modest rate spring with bags of preload (best energy efficiency and lowest recoil acceleration), then increasing muzzle energy necessitates a stiffer spring, which increases recoil acceleration (increased hold sensitivity and a nasty snappy recoil cycle), and also increases piston bounce.

[accuracy lover]

In my mind, the Diana 35 has a timeless classic look and feel, it is somewhat of an archetype of what I feel an air rifle should be, both in looks and apperance. Plus, a soft shooting 10fpe rifle is better than a slammy 8fpe rifle ;-)

I could not agree with you more.
As a kid back in the '80s I came very close in acquiring a brand new one in 0.177 cal but never made it. Therefore this rifle remained to haunt my dreams until this day.
I managed to own newer and better quality spring airguns but the "bug" is still alive and i think it will follow me to the very end of my days.

[jlb73]

PS what was the piston weight ?

ATB

It Was 200g.

I have changed the seal with a Diana 34 model and fitted because it was too tight until the piston nearly move down it's own weight .A nylon ring at the rear end, lube with a mix of molybden , graphite and motor oil.

Nice result with jsb exact : 13,8 J ,regular speed within 3m/s variation

A picture of the 50 year old Lady after some little lifting :
https://imagizer.imageshack.com/img923/2097/ODoWhY.jpg

[Shed tuner]

200g sounds light enough to support a slightly larger port than would normally be optimal for a 28mm bored gun...

[trajectory]

The 35S was the fancy version of the 35, not a more powerful one. It's not like cars where putting an 'S' on the boot gives 100 extra horses.

The Super Meteor and the Meteor are the same mechanicals in the old BSA range but the Super had a Monte Carlo cheek-piece, a deeper fore-end and a thick ventilated recoil pad. It's the stock that made it 'super', same with the Original Diana.. nice stock and sights.

The mysterious Diana 35B is the one that is supposed to be powerful but I cannot see how.

Just been reading this thread & found it very interesting. Just wondering about the above ref To the 35b as supposedly being a bit more powerful than (standard?) model 35, which I hadn't heard before. I had thought the 35b was a bit like the Meteor v Meteor Super. The 35b having a nicer stock with chequering, a moveable rear sight with clip on peep attachment & the four bladed rotating front sight, but I thought the guts were the same.

The E designation on the model 50 has sometimes been said to signify export, is that correct? So, does anyone know what the b designation & the s designation really mean? Or we're they just randomly chosen to differentiate a variation in the range.

Might be able to do some external measurements on a Pre war 35 a post war 35 & 35b if it's of help to anyone.

[jlb73]

After a few hundred shots I tried the jsb exact 4.51 and these are the ones that give the best power with 15 joules (11 ft/lb)!

[evert]

After a few hundred shots I tried the jsb exact 4.51 and these are the ones that give the best power with 15 joules (11 ft/lb)!

Great results! How does it feel to shoot, and how is accuracy?

[jlb73]

Accuracy is very good, quite the same as with my Fein 300 FT(=11 j)
Jsb exact 4,51 is the best choice, 5 pellets outdoor at 50m in F.T. position while setting the scope:

[IMG][/IMG]

[IMG][/IMG]

My gorgeous Diana 35:

[IMG][/IMG]

[Shed tuner]

Looks like a good investment in time.. nice

[evert]

Thats a very nice gun you have built, and some great shooting!

[junglie]

I bought one a couple of months ago, 1976, .177 complete with opens, and generally in very nice condition. I paid £80 which I think was a good deal.
I have another in .22, which isn't so good. Only a matter of time before they come apart!

That was a good deal, always wanted one after shooting a mates in the early 80's & don't worry about the 3 ball trigger once you've stripped & reassembled them a dozen times you can do it blindfold......

[junglie]

After a few hundred shots I tried the jsb exact 4.51 and these are the ones that give the best power with 15 joules (11 ft/lb)!

That's amazing in .177 with good accuracy as your pictures show, well done!