Diana K98 Taming?

[accused]

I like my Diana K98 but being based on the 460 magnum it has a 28mm piston with a 115mm stroke, the transfer port restrictor made it harsh but now removed I cannot get the power sensible. Does anyone know of a short stroke kit for these?

thank you

[Black Beard]

I assume that the piston has the same front end as a 48/52. Tinbum used to do a piston extension for a Diana 52 that might help a little. Can't see them on his website.

I'd try a less powerful spring like a Titan No 10 (need to set it up with about 15mm preload).

BB

[accused]

Thanks I thought tbt did do one but couldn't find it, yes same 28mm front so could have worked.

[Barryg]

Although it has a 52 piston the ABT has a different setup and I was wondering if the ABT would slide back far enough to engage in the slot 0n the cylinder as the piston stem might stop short when the trigger was engaged if a extended piston head was fitted.

I get a nice result on my 460 by using this factory spring with no restrictor, I get a consistent 11ft/lbs

[accused]

With the factory spring I got way too much with no restrictor in the transfer port! I have lot of springs and it nearly behaved with a 77 spring but it needs a long one with that stroke.
I killed the super thin restrictor removing it so I need a spring or extension to cure it now.
I suppose if all else fails it can go to a good tuner to get the power right and stop the awful twang.

[Barryg]

With the factory spring I got way too much with no restrictor in the transfer port! I have lot of springs and it nearly behaved with a 77 spring but it needs a long one with that stroke.
I killed the super thin restrictor removing it so I need a spring or extension to cure it now.
I suppose if all else fails it can go to a good tuner to get the power right and stop the awful twang.

You are right about a long spring my spring has 40 coils. The springs seem to have changed over the years my 460 is over 10 old and never twanged from the start, I would say try to get a better softer kit as the ABT seems to rely on the long stroke to engage and they can be nice as they are with the long stroke.

[Shed tuner]

for variety I put a delrin plug down the end of my comp tube of my K98 and drilled a 3mm port through to shorten the stroke. Worked quite well, but it will be a bugger to remove !

[Barryg]

for variety I put a delrin plug down the end of my comp tube of my K98 and drilled a 3mm port through to shorten the stroke. Worked quite well, but it will be a bugger to remove !

Have you checked that the ABT is working?

[accused]

I'm getting there with the original guide cut shorter to allow a top hat, a ptfe sleeve, a 77 spring that needs a bit more off it...much smoother and quieter

[Shed tuner]

Have you checked that the ABT is working?

yup, I'm 100% sure it works; I put it in my spares box to make sure it didn't get damaged

[accused]

Yes my ABT is removed to, I can't "bear" them

[tinbum]

We made an extension for dianas for a while, but the abt made it difficult for some. The whole point of our kits is anyone can fit one with ease, so we decided to stop.

I think you're on the right track with your too hat and spring, our early short stroke of a compression tube "plug" also works better than it should.

Once done it's a satisfying gun to shoot

[Barryg]

LOL. Some of you guys like to live dangerously with no ABT

Personally I would not ruin a nice gun by short stroking it and defiantly leave the no noise ABT on it, it's much more fun getting these guns shooting nice just by tuning and being a little patient is much more satisfying once you get it right, effortless cocking super smooth and a pleasure to shoot

[Shed tuner]

LOL. Some of you guys like to live dangerously with no ABT

Personally I would not ruin a nice gun by short stroking it and defiantly leave the no noise ABT on it, it's much more fun getting these guns shooting nice just by tuning and being a little patient is much more satisfying once you get it right, effortless cocking super smooth and a pleasure to shoot

lol.. taking it from 118mm to 100 is not short stroking - it's barely medium stroking.

I would have prefered the ABT in place, but holding onto the underlever is not too challenging. effortless cocking and super smooth shooting is easy enough to acheive, your are right. However it's the 10 second long firing cycle that goes with the 115mm stroke that some of us don't like

[Black Beard]

The longer cycle is good training. Stick in 50g of piston weighs and it will be even slower.