Piston seals Vs Lubing.

[Big Daddy]

We all know that air rifles need tuning to improve performance. For those of us who have tuned our guns or have had our guns tuned, we know the difference. For some, just high velocity with smooth firing means performance while for others maximum velocity coupled with high accuracy and smoothness. While still for others, average velocity, but smoothness with accuracy and are happy with a max distance of 15 meters. The common denominator is “smoothness”.
We know that one of the major areas of tuning is the power plant. Friction plays a major factor (among others).

Theoretically, almost all spring have an average of 30% friction inside the power plant. One of the reasons for tuning is to reduce this friction as much as possible. Primary friction area is the piston washer and the chambers inner wall. Friction can be significantly reduced by lubing the internal parts mentioned, thought it is not that easy to lube inside so often. Also excess lubing might have side effects.

Now keeping lubing in mind, the question is, does lubing lie in the relationship between the seal and the type of inner wall? Does this depend on the type of washer / seal opted for?
For a “mirror smooth” inner wall, wouldn’t leather seals suit best?
My take is, the lather seal surface will always be rough, hence when the rifle is being cocked, lube stuck to the leather will lube the chambers inner wall acting like a lube brush. Therefore every time you fire your gun, you can be assured of proper lubrication.
On the other hand, if it is the synthetic seal, wouldn’t is wipe clean a smooth wall and deposit the lube in the front end? More like your shaving razor. And every time you shoot, wouldn’t it become more and more “dry”?
If a syntactic seal were to be used, wouldn’t a mild “matt finish” (matt enough to allow lube deposits but not act like a file) wall texture work wonders for a syntactic seal in that the seal cannot make a ‘clean sweep’ of the lube?

Gentlemen, your views please.

Gentle giant (PKJ), your’s in particular .

[fantumfan2003]

Bade Pappa,

Fantastic topic you have started here....

Objective of tuning is SMOOTHNESS and not always POWER. Sometimes tuning reduces POWER but increases SMOOTHNESS. Which is a desirable attribute in a springer

We all know that air rifles need tuning to improve performance. For those of us who have tuned our guns or have had our guns tuned, we know the difference. For some, just high velocity with smooth firing means performance while for others maximum velocity coupled with high accuracy and smoothness.

Springers shooting in the 825fps range in .177 are the smoothest to shoot, any faster and they just behave like wild, untamed, whatevers.

While still for others, average velocity, but smoothness with accuracy and are happy with a max distance of 15 meters. The common denominator is “smoothness”.

Yes friction is to be minimised. But there is friction in many places in the springer, not just the piston seal, which is actually not so big as a percentage of the overall. Seals like Diana are self lubricating so its a non issue. Besides even if lubes like silicon oil or other modern specialised lubes do enter the tube, they will not cause dieseling or detonations

We know that one of the major areas of tuning is the power plant. Friction plays a major factor (among others).

Theoretically, almost all spring have an average of 30% friction inside the power plant. One of the reasons for tuning is to reduce this friction as much as possible. Primary friction area is the piston washer and the chambers inner wall. Friction can be significantly reduced by lubing the internal parts mentioned, thought it is not that easy to lube inside so often. Also excess lubing might have side effects.

Now keeping lubing in mind, the question is, does lubing lie in the relationship between the seal and the type of inner wall? Does this depend on the type of washer / seal opted for?
For a “mirror smooth” inner wall, wouldn’t leather seals suit best?
My take is, the lather seal surface will always be rough, hence when the rifle is being cocked, lube stuck to the leather will lube the chambers inner wall acting like a lube brush. Therefore every time you fire your gun, you can be assured of proper lubrication.
On the other hand, if it is the synthetic seal, wouldn’t is wipe clean a smooth wall and deposit the lube in the front end? More like your shaving razor. And every time you shoot, wouldn’t it become more and more “dry”?
If a syntactic seal were to be used, wouldn’t a mild “matt finish” (matt enough to allow lube deposits but not act like a file) wall texture work wonders for a syntactic seal in that the seal cannot make a ‘clean sweep’ of the lube?

Gentlemen, your views please.

There is very little that needs to be done in word class springers like TX, HW and most Diana's. The TX200 does not need any tuning at all and is definitely the smoothest shooting springer in the world out of the box. Its the Indian ones that will benefit most as their quality these days is nothing to note. IHP, included I am afraid.

Just my $0.02....

Ghost who walks....

M.

[Big Daddy]

yes Fantumfan, you are right about the TX / HW. Point is the Indian ones. Thought this post would throw some light for owners of Indian rifles. Recently shot with a Diana 34 classic. Quiet an old gun but it was 'super smooth' though not opened for ages.

BD

[pkjeetesh]

BD....we can discuss endlessly on the thread you just started above...each man his own gun/and how he likes it and what he wants it to be....like what JM said

Only care about velocity? Run a spring on one sloppy guide spaced to the max and no lube.You will get velocity and the gun will shoot like a bucket of bolts. Put two tight guides on it and a correct tight fitting seal, with some lube and it will shoot like a dream if the receiver or comp tube is true. Should be common sense.

from my experience...

1. Modern synthetic seals require very little lubrication, only a thin layer of moly on its' lip...it must be correctly sized though
2. To avoid the lather effect, a cross hatch pattern has to be developed on the inside of the compression chamber...this keeps the lube in tact...i did that to your Canon
3. Some more moly only on the outside of piston bell and you are ready to go...
4. A thin layer of open gear grease on the OD of the spring/or nothing at all if you install tight fitting guides will reduce or even eliminate the twang

reg

pkj