Squashing a spring

[rg627]

Hello

Just a quick question for the more experienced/knowledgeable than me....

In the past I have heated up and squashed coils down on springs, also cut springs and then squashed the last coil to flatten it successfully.

I want to do some experimenting with a gun. I'm trying to reduce felt recoil and more importantly, reduce hold sensistivty.

If I squashed rather than removed a coil, could I heated it back up again at a later date and pull the squashed coils back to normal length? Would the spring be ruined or would it revert back to it's normal function? It sounds a daft question, but has anyone tried this successfully. I need some advice of the physics experts....

Thank you

[Hsing-ee]

I think the 'temper' of the coil is knackered by the heating.

It would be in bad temper if you re-heated it and pulled it out, and might collapse again or break. Never mind the wonky shape, as it would be hard to get the perfect regular spiral it had when it was wound.

It also sounds 'cruel and unusual' and not the sort of thing a civilised man should do to a spring, just IMHO.

Maccari in the US likes to use shorter, stiffer springs and then space them to get the right power. No cutting or heating or crushing involved.

Good luck!

[rg627]

Good point about the temper...

Reason I ask,. My 99 runs best at 9_10 ft lbs in 177

I wonder if lowering the power slightly would help reduce hold sensistivty in my lgv? Is trimming the spring a coil a recipe for disaster? I know it depends on piston weight etc ... This is where the science all gets a bit above me....

Just wanted to see if lowering power has any effect on hold sensistivty

[Hsing-ee]

Good point about the temper...

Reason I ask,. My 99 runs best at 9_10 ft lbs in 177

I wonder if lowering the power slightly would help reduce hold sensistivty in my lgv? Is trimming the spring a coil a recipe for disaster? I know it depends on piston weight etc ... This is where the science all gets a bit above me....

Just wanted to see if lowering power has any effect on hold sensistivty

Usually it does as there is less kinetic energy bouncing around. The other thing to do is to add lots of weight to the rifle, a heavy scope, scope mount, drill holes in the stock and embed lead weights in it ...

Ask 'shed tuner', he is the master of the low-recoil tune. There's a weird relationship between pellet-fit, transfer-port-size, piston weight, spring power, spring stiffness, the characteristics of the sealing washer, the lube, the weight of the stock and probably the phase of the moon that influence all this.

I think the Walthers are designed for over 12 fpe and have odd transfer ports, that is why the tuners avoid them. I have not heard that they are hold-sensitive though, they are heavy and have long soft strokes so they should be relatively easy to shoot. The HW99 should run well at 11 fpe in either calibre and not be hold-sensitive - maybe you need a softer spring or something. How many different types of pellet have you tried? Have you had someone check your technique?

[rg627]

Thanks pal

I did wonder why I wasn't finding much the information on lgv tuning.

It's for informal target, plinking so I'm not power mad on this one. Shoots quite nice but a pig with hold sensistivty, more so than any of my other springers.

I just can't get the knack of it no matter what hold/ grip/ artillery hold I use. Every technique that has helped me in the past seems not to work on this one...

[Hsing-ee]

Thanks pal

I did wonder why I wasn't finding much the information on lgv tuning.

It's for informal target, plinking so I'm not power mad on this one. Shoots quite nice but a pig with hold sensistivty, more so than any of my other springers.

I just can't get the knack of it no matter what hold/ grip/ artillery hold I use. Every technique that has helped me in the past seems not to work on this one...

Take it to the Springer Bash and let the experts diagnose it. I had a FWB Sport which I never felt was as good as it should be, lent it to one of the experts and he diagnosed it with a slightly undersized piston seal, which was new at the time but not OEM. I had no idea! The Walther shouldn't be very hold-sensitive and there is no reason why you should need to drop the power significantly; even if you did the problem may still be there just not so magnified. I would check for piston weights, broken spring, leaking breech seal and leaking piston seal and see if something turns up.

[rg627]

Very tempting, the boinger bash...

I want to get it running nicely as it's a lovely rifle other than that

[Mr. Gen]

I like to start by collapsing a few coils rather than cutting them off. You can then experiment with having the weight travelling or stationery. It can often make a difference to power and/or felt recoil.

[bozz]

Hi have you actually checked the power as it might have had someone tamper in the past. They are dead easy to strip and work on. All the best Graham.

[rg627]

Hello guys.

Thanks for the replies. Not tesed yet as my Chrono is proving tempremental at the mo. I'll try at the club next time I'm there.

I've put in a diy piston liner, has stopped the slight twang but seems no better or worse than it was before for sensistivty. I don't think it's this.

Holding hand on a rest on bench. Fore stock sat on flat open palm. Trigger hand has slight pressure squeezing grip between fingers and palm. Thumb not touch touching stock. Head lightly touching stock. Butt just lightly touching shoulder. Gun free to move when fired.

I'm I missing something obvious,. This technique works with my other springers.

Not sure where I'm going wrong

[Shed tuner]

technique doesn't sound like the problem, but is it innacruate, or hold sensitive ? If you shoot it as you described, with a very consistent hold, and it's still innaccurate, it's not hold sensitiive - it's innacurate !

So now to answer the why is it innacurate..
i) give the barrel a good clean
ii) try a few different pellets - JSBs, H&Ns, superdomes are all worth a crack - alowwing a couple of dozen shots each tiem you switch got the bore to adjust to the lead composition of the new pellet
iii) shoot over the chrono - is it consistent - if not may need a new piston seal or breech seal, or a busted spring
iv) knackered scope - try another
v) let someone else try the gun
vi) the barrel may have a problem - e.g. crowning.
vii) come to the springer bash (actually, just do that anyways) !

[StellaArtois Sr]

What I would recommend is that if you are close to your preferred FPS then I would compress a spring rather than cut it. I did find when I was close I decided to remove half a coil and ended up having to use pre load washers to bring it back up.
Once you are close to your target a little spring makes a big difference.

[rg627]

Just gave the barrel a good clean. Seems much better. I'll get some more lead down he barrel and see how I go from there

Cheers

[Shed tuner]

Just gave the barrel a good clean. Seems much better. I'll get some more lead down he barrel and see how I go from there

Cheers

best try the simple stuff first