Another common question is: "¿What IS proper lubing?"
Still some others that think that offense is the best defense, ask: "Why do you lube your pellets? I shoot them straight out of the tin!"
;-)
Fair enough, we all know that each rifle is different but, still, in my years of professional gunsmithing I have found two basic "truths" that apply in airgunning:
1.- Pellets fly best at or below the 875 fps region
2.- PROPER lubing of pellets AND rifles DOES make a difference.
Perhaps in some guns the difference is small enough that it is impossible to measure, but IMHE, there is always a difference.
My mind follows very peculiar paths; "tortuous" would be the word chosen by my wife, but I prefer to think that I am always looking at all problems, sometimes simultaneously, from different points of view. Just part and parcel of being a Gemini, LOL!
In any case, as a pre-requisite experiment to a new design of piston that I need to tackle a complete "re-do" of some military replicas, I wanted to start by testing the new design in a well known platform. Normally, at this stage I would start looking into the classifieds and the whole thing would take some time but, luckily, I had already sourced it some months ago and that was covered. And no, it is not a DIANA.
All good experiments start by laying a "baseline". A point from where all other comparisons are going to be set-up, and so I proceeded to test the gun, after being in storage for some months.
Starting with a good 20 shot string just to bring the gun back to "operational" status, I started chronoing pellets that I knew usually shot well in that brand of airgun.
They are reputed to have bores on the "generous" side, so the first pellet chosen was the JSB Exact 8.44/4.53
As an aside, here I have to remind everyone that the numbers stated for the head size, in the case of JSB, are not exactly measurements taken from the heads of the pellets, but rather obey an indirect method of measuring where they test in different barrels and then assign the head size of the barrel that shoots them best.
I also added to the mix the H&N BFT, both in 4.50 and 4.51 head sizes. My experience is that the head weighs enough to be "upset" by the pressure blow and have a good contact with the rifling.
My DIANA guns (54 and 430L) prefer the 4.51 size, but some other guns prefer the 4.50
Finally, I added the QYS pellets that have been taking most of my time lately. Very uniform, and accurate when the bore likes the land-riding design of the head. Of course, creating a land riding pellet starts with the premise that people know that the design is handicapped in the power it can take. We'll get to that later.
So, all in all, 5 pellets that I consider the best among the current production runs.
AND then I started taking apart the "test mule".
Horror of horrors!
Gobs and gobs of black tars of different densities and viscosities. :-P Dughhhhhh!
It was going to take 3 hours to clean this mess!
But then, looking at the other side of the problem: ¿WHEN would I EVER get a better chance to test what has become the "traditional American grease tune"?
I was not going to do one of those tunes, LOL! .
I do not even have those heavy lubes at hand anymore! It's been YEARS since I stopped using those heavy petroleum derivatives. Paraphrasing a friend "That's dinosaur juice!"
So I closed again the gun, and got the pellets out to create that "baseline".
And a lightbulb flashed in my head: If I am going to compare lube jobs, why not compare also pellet lube jobs?
And the 5 became 7.
The test was simple enough once all the parameters were laid down, we would look at MV and KE of the 7 pellets chosen with the "grease" lube-tune and then clean the whole thing with lacquer thinner, and re-lube with Ultimox 226.
Because we had pellets with different leads and different lubes three shots were allowed between each change of lube, and 5 pellets between each change of lead. And then 10 shots were taken for the record for each pellet.
I did find that the pellet lube was a more important change than the change of pellet lead. Which is an interesting conclusion in itself. Many shooters believe that you need to completely clean the barrel and then take 20 shots with each different type of pellet you test, what I have found over the course of years, is that if you lube your pellets you need to worry more about change of lube than about the change of pellet/lead itself.
I have also found that most bores exhibit a definite preference for certain lubes. I used to use three lubes, but for a few years I have only used two now: Pledge and T-9. Both products that come from the non-shooting world, are inexpensive and widely available, and hold no "secret sauce".
Well it was a rainy and depressing day anyway, and I had just delivered a project to one of our Armed Forces, so I had the time before tackling other projects.
I shot the full 100+ shots test with the "Traditional Lube", and then spent, literally, a couple of hours cleaning that stuff, then re-lubed with Ultimox 226 and ran the whole test again.
And, here are the results:
For starters, you can see that for identical pellets in the same rifle, under the same conditions, the difference in lube can mean between 2 and 8 fps in the case of the "dinosaur juice" lube-tune and between 2 and 5 fps in the case of the Ultimox lube-tune. In both cases, the fact that the difference was smaller for the H&N 4.51 pellets, tells me that we should try to achieve maximum accuracy with those pellets from the H&N family.
We can also notice that this bore seems to prefer the Pledge lubed pellets.
Some may say: 2 to 8 fps is not worth the work to lube pellets. While that is true from the energy standpoint, when you look for maximum precision and accuracy, those 2 fps can mean that the harmonics in the barrel "jive" to a good tune or produce a cacophony. Many times have I found that a harmonics tuner tuned to a "naked" pellet needs to be moved a tad when the pellets get lubed. And that some bores that "do not want to shoot" as the user wants, in reality are just asking for the pellets to be lubed to start shooting up to snuff.
Now, if we move ACROSS the lube-tunes of the SAME GUN, there are other things we can conclude, and basically, it's that if you are still using the old lubes, you are leaving a LOT of energy on the bargaining table. In other words you are not getting the efficiency that you COULD be getting, at least in a finely crafted gun like the one on the experimentation table.
Kinetic Energy gains of between 15% and 22% are nothing to sneeze at. And if the "quality" of the shot cycle was about the same, lowering the Ultimox tuned rifle to the same energy level as the Dino-juice tune, will certainly enhance the quality of said shot cycle. In brief: There are less inefficiencies that go to produce twang, vibration, heat and other residual energies (like noise) when using Ultimox.
Now, while some GAINS are impressive, you still need to consider which pellet will yield the best result at the target, and that is something we will be exploring soon.
Prime candidates for testing, especially at longer ranges would be:
H&N BFT both head sizes, as well as the Heavy QYS domed all lubed with Pledge, need to be tested, also the JSB 8.44/4.53 needs also a thorough testing and a testing with Pledge.
We can safely assume that the QYS light Streamlined is simply a bit light for the increased power transfer, and so it is deforming in the barrel, and loosing all efficiency. This may NOT pass, once the total power yield has been turned down to the proper level for FT.
Anyway, now that the questions about lubing (pellets AND rifle) have received an answer (limited to a sample of 1, agreed, but at least it is more than what we had before), it will be up to each shooter to decide if a lubing job of their gun and pellets is warranted or not.
Getting a uniform MV with low SD's certainly is a requirement to have a good performance at the target, but it's not a sufficient condition. Let's hope the weather will allow us to test these pellets outdoors soon.
Once that is done, we can continue with the next phase of the development.
Keep well and shoot straight!
HM