I like to preset mainsprings.
As supplied by the manufacturer they all usually have a standard ID/OD for the same spring.
Probably due to different locations in the batch tempering oven, they may develop different ID/ODs in use.
A spring that appears tight on the guide when there is no spring load (when the gun is uncocked) may actually be quite sloppy after it takes a set.
This introduces the possibilty of shooting twang and spring kinking.
Kinking does stop the spring twang but, I suspect, at a loss of some power.
By setting up the spring to coil bound on an allthread rod one discovers the OD when the gun is fully cocked (will it bind in the piston?).
Leaving the spring coil bound overnight on the rod will give a better idea of final ID/OD and make it easier to insert into the gun if there will be serious preload such as a Weihrauch or Wischo/BSF air rifle.
I have had some new 714" OD .105" wire springs from the same shipment stay at .714" and others set as high as .724" .
If one knows what the mainspring's final dimensions will be when the airgun is cocked/uncocked and the spring is broken in (or preset), it is possible to make better choices on guide diameters and piston sleeving.
Presetting Mainsprings
Set Mainspring Testing.
Funsupply has test results from leaving German and British airguns cocked posted on their website.
Left cocked for 24 weeks they lost an average of 26.1% of their velocity.
Left cocked for one week they lost an average of 2.1% of their velocity.
I suspect that velocity loss from presetting overnight would be statistically insignificant.
I note that the tests were on BSA, FWB, Webley and Weihrauch airguns.
I am not sure how Chinese springs would fare under similar testing.
The full test results can be viewed at
http://www.funsupply.com/airguns/cocktest.html
Left cocked for 24 weeks they lost an average of 26.1% of their velocity.
Left cocked for one week they lost an average of 2.1% of their velocity.
I suspect that velocity loss from presetting overnight would be statistically insignificant.
I note that the tests were on BSA, FWB, Webley and Weihrauch airguns.
I am not sure how Chinese springs would fare under similar testing.
The full test results can be viewed at
http://www.funsupply.com/airguns/cocktest.html
What it failed to mention was what springs were used, standard factory?
These are all cheap air rifles using reasonable quality springs.
Also silicon and metal to metal is a big no, might just as well put grinding compound in!
There are springs and there are springs, all differ with the material they are made out of and just as important how they are hardened and tempered- If they collapse, they are too soft. If they break they are too hard.
On any spring format compression, V, coil or tension the very first time it is worked will have the greatest effect. In this case a compression spring fully compressed for the first time will reduce in lengh and possibly gain o/d but should not, time anything from 10 mins to a day.
I work with springs every day in fact i am one of four in the world who specialise in certain types. Some are as good as when first made in the late 1700's and have been fully compressed ever since fitted!
These are all cheap air rifles using reasonable quality springs.
Also silicon and metal to metal is a big no, might just as well put grinding compound in!
There are springs and there are springs, all differ with the material they are made out of and just as important how they are hardened and tempered- If they collapse, they are too soft. If they break they are too hard.
On any spring format compression, V, coil or tension the very first time it is worked will have the greatest effect. In this case a compression spring fully compressed for the first time will reduce in lengh and possibly gain o/d but should not, time anything from 10 mins to a day.
I work with springs every day in fact i am one of four in the world who specialise in certain types. Some are as good as when first made in the late 1700's and have been fully compressed ever since fitted!
Sorry Jon!
BSA, Feinwerkbau, Webley and Weihrauch are not "CHEAP" airguns.
Most of the work that I have done on mainsprings have been with Diana 25/27/35 and BSF 55/60/S70.
When you sober up, please repost.
Most of the work that I have done on mainsprings have been with Diana 25/27/35 and BSF 55/60/S70.
When you sober up, please repost.
The oil mixture use is silicone and moly. It is the moly that does the metal to metal lubing. The silicone oil is just a carrier. Springers are prone to dieseling, silicone oil is less volatile/combustibles than other oils, thats why it is used.Jon wrote:What it failed to mention was what springs were used, standard factory?
These are all cheap air rifles using reasonable quality springs.
Also silicon and metal to metal is a big no, might just as well put grinding compound in!
There are springs and there are springs, all differ with the material they are made out of and just as important how they are hardened and tempered- If they collapse, they are too soft. If they break they are too hard.
On any spring format compression, V, coil or tension the very first time it is worked will have the greatest effect. In this case a compression spring fully compressed for the first time will reduce in lengh and possibly gain o/d but should not, time anything from 10 mins to a day.
I work with springs every day in fact i am one of four in the world who specialise in certain types. Some are as good as when first made in the late 1700's and have been fully compressed ever since fitted!
What you say about springs are true for high quality and lightly loaded springs where you are not overloading the spring. The spring material is kept in their elastic state. However, like you say, I doubt that the spring material use in non-critical applications as in a springer, are of high quality. In those test cases, with high power springer, their springs are over stressed when cocked. The spring material will creep causing significant permanent change in length if left cock over long period of time.
Lost in power in high power magnum springers are real if they are kept cocked over a long period of time. High quality aftermarket springs might perform better. On the other hand, a springer like the Quest 500 which is lightly load, since it uses the same spring as a Quest 1000, could be left cock forever without losing any power.
Last edited by ETA on Fri Dec 30, 2005 8:09 pm, edited 1 time in total.
Jon..they said silicone not silicon...big difference between the two...Jon wrote: These are all cheap air rifles using reasonable quality springs.
Also silicon and metal to metal is a big no, might just as well put grinding compound in!
The former is polymer, used in lubricants, and synthetic rubber...
the later is well to oversimplify...sand.
I'll own up then and stand corrected silicon/silicone.
Still wont change my view these are cheap and made to a price. Not everything English or German is class as i can prove.
Yes i have had and worked on nearly everything decent for the trade and all manner of people worldwide and still got left a BSA Goldstar 1994 modded, AA TX200 walnut 1994 show piece where do i start, Original 52 modded of course, the only cheapies i have left somewhere.
Basically the above new unmodded are 1/2 to 1/10th of the price of a good rifle worth shooting.
Each to their own, i would not bother shooting if i had to rely on above three rifles, yet alone BSF's The 48, 52 and 54 are respectable in Diana, must be in a third world over there, there again each to their own.
Still wont change my view these are cheap and made to a price. Not everything English or German is class as i can prove.
Yes i have had and worked on nearly everything decent for the trade and all manner of people worldwide and still got left a BSA Goldstar 1994 modded, AA TX200 walnut 1994 show piece where do i start, Original 52 modded of course, the only cheapies i have left somewhere.
Basically the above new unmodded are 1/2 to 1/10th of the price of a good rifle worth shooting.
Each to their own, i would not bother shooting if i had to rely on above three rifles, yet alone BSF's The 48, 52 and 54 are respectable in Diana, must be in a third world over there, there again each to their own.
Third worlds don't have airguns. They throw sticks and stones. If they are lucky, they might find some rubber bands for a sling shot.Jon wrote:I'll own up then and stand corrected silicon/silicone.
Still wont change my view these are cheap and made to a price. Not everything English or German is class as i can prove.
Yes i have had and worked on nearly everything decent for the trade and all manner of people worldwide and still got left a BSA Goldstar 1994 modded, AA TX200 walnut 1994 show piece where do i start, Original 52 modded of course, the only cheapies i have left somewhere.
Basically the above new unmodded are 1/2 to 1/10th of the price of a good rifle worth shooting.
Each to their own, i would not bother shooting if i had to rely on above three rifles, yet alone BSF's The 48, 52 and 54 are respectable in Diana, must be in a third world over there, there again each to their own.
Seriously, you must be kidding, why would folks in the third world blow their money on frivolous toys like airguns? They are more likely to have real firearms.
OK Jon, why don't you enlighten us with a list of nice sporter springers that are worthy for you to shoot?
Last edited by ETA on Sat Dec 31, 2005 10:54 pm, edited 1 time in total.