Spring shortening -Photo attached - How shot is too short?

[Staffy1]

I bought aHW99 on here the spring had been shortened ( see photo) by some one previously. I fitted a better fitting HW spring guide ( not top hat) and a slip washer. Guns running pretty close to limit and I really only need 10-10.5ftlb ish I was going to get another coil cut . Will this cause issues ie how short can you go ?. Guns dieseling slightly but even if it settles bit too close to upper limit for my liking .

 

[Deejayuu]

How much pre load is there please?

 

[junglie2022]

Just a coil at a time if I were you then refinish it when it's a tad over 10.5.

 

[JimPlas]

We need more information to be able to answer: what calibre and what pellet?

 

[Staffy1]

How much pre load is there please?

Gotta push pretty hard to get the end block back in , doable by hand but bit of force required

 

[Staffy1]

We need more information to be able to answer: what calibre and what pellet?

.22 16.44 grain Webley pellet

 

[Staffy1]

You know what guys ive just googled pellet weight for Webley pellets its 14.66 grains not 16.44 ! So 11.3 ft lb , i still want it a bit lower though lol! As ive stripped gun again I think ill cut one coil off should be where i need it doh!

 

[Ashf9999]

Go by half, if not quarter coils at this stage then. You’re at the point it won’t take much.

 

[10/10]

Probably better to collapse half a coil.
As when you cut and Re-dress the end they can end up a bit shorter than intended

 

[ricardolamos]

Just shortened a spring on a TX200 for a clubmate and half a coil off(5mm length reduction) reduced power output from 11.9 to 11.1 ft.lbs.
Gun is now much more pleasant to shoot.

As others have said, don't take too much off to start with.

Collapsing a coil is obviously easier but generally not seen as such a good option as it is usually done at the piston end and effectively adds moving weight which may increase felt vibration/recoil.

You need to keep some preload otherwise at the end of the shot cycle the spring is more likely to vibrate but it sounds like you can remove some length and still maintain decent preload.

Sounds like you have some lubricant ahead of the piston seal if you are getting dieseling. Best to remove it as repeated dieseling can damage the piston seal. Tony Leach recommends a gain of rice sized drop of STP petrol treatment mixed with treadmill silicone oil smeared around the edge of the piston seal and I have found this works very well.