here is an article I am working, on, I would appreciate your feedback.
About Pellet Numbers and Pellet Testing
The first thing you need to know is that competition air guns used in the Olympic disciplines are .177 caliber, which is equal to 177th thousandths of an inch. The metric equivalent to .177 inches is 4.50 millimeters, therefore the European caliber designation is 4.5 mm.
Next, you should know that the smallest quantity of match pellets are typically packaged as 500 pellets and are in containers called tins. When ten tins are packaged together, they are called a sleeve. A sleeve contains 5,000 pellets and weighs a little more than 6 pounds. Five sleeves packaged together are called a case. A case contains 25,000 pellets and weighs about 32 pounds. Case quantities are normally bought by schools, clubs, very serious competitors, or those stocking up early for Y3K.
So much for packaging. Next, you need to know that these .177 caliber or 4.50 mm match pellets are made in different sizes.
As a way of refining accuracy, and to most perfectly fit an individual group of pellets to the exact size and characteristics of your gun barrel, pellets are made in different head sizes. Head sizes start at 4.48 mm and continue through 4.49, 4.50, 4.51, and 4.52 mm. These sizes are determined by the various size molds used to create the pellets in the manufacturing process. But, you ask, isn't one .177 barrel the same size as another .177 barrel? No, not really.
In the barrel manufacturing process, the tolerances are such that the finished size of the lands and grooves of the rifling, will vary enough from one barrel to another that, while one barrel coming off of the assembly line might prefer the undersized pellets of 4.48 mm - the next barrel might be happier with oversized pellets of 4.51 mm.
In a perfect world, you would discover which head size fits your gun and that would always be the perfect pellet for your gun - but, we all know we don’t live in a perfect world. Nonetheless, a myth has arisen in the shooting world saying that a specific pellet head size is the only information you need to know to obtain maximum accuracy from a particular target airgun. This myth is derived from a misunderstanding of a small piece of paper that comes with every target airgun sold, that paper is called a test target.
The airgun manufacturers (Anschutz, Walther, Steyr, FWB, Morini, etc.) include a test target with each new airgun showing a very small group shot from that specific airgun. Generally, scribbled beside the group will be some initials denoting the mfg of the pellet (H & N, RWS, JSB, or Vogel) and a head size diameter (4.48, 4.9, 4.50, etc). It is a profound misunderstanding of this test target which causes so much confusion for parents, athletes and coaches.
Unfortunately, the conclusion of proper head size pellets for this particular airgun is drawn when the new owner opens up his or her prize new airgun and looks at the owner's manual for guidance and sees the head size written on the test target. The owner immediately thinks that it was selected by the factory as the perfect size pellet for use in this airgun, somewhat akin to Moses bringing the 10 commandments off of Mount Sinai. The reality is that head size on a factory test target has about as much relevance to your final decision on what is the most accurate pellet for your airgun as Bugs Bunny making that proverbial left turn in Albuquerque.
The test target is nothing more than a validation from the factory that this particular airgun is capable of shooting well. The factory IS NOT trying to determine the best pellet for your gun. In fact, as we will see in a moment, they cannot do this. What the gun factories want to do is put a sample of various pellets through their guns to see if they are shooting to their accuracy expectations. The test targets are shot with a group of five pellets. If they shoot the one group of five pellets and they get a great looking group, you can bet the next thing that gun will see is the inside of a packing box, not shooting more five shot groups of pellets.
Of course they will not always get a great looking group on the first attempt and often will shoot two or three different five shot groups of pellets to assess the accuracy of the gun/barrel combination. From that first two or three groups, they will take the best looking group, scribble down the manufacter and head size on that test target as a verification that it shot well. Then that airgun goes off for final packaging and is shipped to an airgun dealer near you.
If they shoot the first four groups and none of the groups are as tight as they should be, then they will shoot another sample of four groups possibly on the opposite extreme of the pellet size spectrum. Normally, for air rifles, one or more of these groups will be able to hold an unfired pellet up by skirt, when holding the target horizontally in the air. As soon as they find a good looking group, that target will go out with the gun. If none of these attempts show accuracy, then the gun will go back to have its barrel or regulator checked before coming back to the test range. The point is, shooting test targets are not attempts by the factory at defining what shoots well in their barrel, but only that their barrel does indeed shoot well.
Now then, if this head size number indicated on your gun’s test target is not the key to the accuracy then what is? How do you know what pellets you should buy? To really get true information requires testing your airgun from solid rest with a variety of head sizes and lot numbers. Lot numbers you say? What are those? Lot numbers are what are used by manufactures to differentiate between various groups of pellets having different production characteristics.
In firearms ammunition there are a lot more variables that can make-up a lot number change. Anything that is different in the production requires a new lot number. A change from one group of primers to another, a new box of gun powder, a change in brass, a change in the roll of lead wire used to make the bullet, a change in the adjustment of the machine, even a simple tweak will necessitate a new lot number. Often this means that single machine operating in a normal 8 hour work day could produce 5 or more different lot numbers.
For airgun pellets, there are really only two variables that create a different lot number, a change in the lead wire or a change in the machine adjustment. For us at Vogel USA, if everything goes well and an entire roll of lead wire runs through the machine without any machine tweaking taking place, then a lot will not be any larger than 12 sleeves, or approximately 60,000 pellets. If production is stopped in the middle of a roll of wire and a machine adjustment is made, then that creates a new lot number. If we stop again and make another machine adjustment, then that creates another new lot number. So you can see that its possible that lot number could cover only 2 or 3 sleeves of pellets.
To determine what a given pellet's lot number is, we normally only have to look at the tins, often they are stamped on little stickers on the bottom of the tin, and they will also be found on the corresponding sleeves and cases. It is important when choosing lots to be tested, that you determine if the supplier has a large enough quantity on hand of each lot number you test to actually supply you with that lot number in the event you choose it as the best shooting lot in your gun. Often, a supplier will have to hold back those lots being tested until you make your final purchase, so they won't sell out of the lot you eventually choose. In fairness to the vendors, you should do your pellet testing as soon as possible upon receiving the sample lots, so as not to tie up his inventory of pellets for weeks on end.
Next, we will talk separately about rifle testing versus pistol testing, since the have two vastly different requirements.
About Pellet Numbers and Pellet Testing
Moderators: pilkguns, m1963, David Levene, Spencer, Richard H
-
guest5
The foam layered individually packed pellets are made on the same machines and tumbled in the same tumblers. I really don’t know if there is any extra visual screening/examination of these before they are placed in their foam pocket. In theory they should shoot better, since they are not constantly touching, rubbing, sliding around against other pellets in the bulk packed tins. Mentally, I think some people feel better shooting with individually packed pellets. However, practically experience has shown that the bulk packed pellets shoot just as well (or not) as individually packed pellets based on their barrel fit by lot number. They certainly do not shoot better in the same proportion as their increased cost. We may offer these eventually though, just because there are people who will pay for the psychological advantage
Great info, Scott. Thanks!
Understanding that the factory test target doesn't tell us much, it makes me wonder if one shouldn't spend an hour or two to find the right combo for your pistol or rifle. In additon, I was cleaning out some files today and found my pellet tests for my old FWB Mdl 2 and C20. The results were shocking.
In short, I tested both of those pistols with multiple pellets and multiple velocity settings. For the Mdl 2, I found a pellet and velocity combo that shot groups that really looked like a single pellet. With the C20, I never quite got as good a result, even though it had the separate chamber and should have been less resistant to temp changes. It is important to say that with other pellets and especially with different velocity settings, the results were much worse. Some were so bad, I would have returned the pistol for repair.
The point of this is that I've never touched the velocity setting on my Morini APs. I kind of wish I had done so now. How do I know that the factory has it set for the optimum velocity for the pellets I'm using? I don't.
Please don't deluge me with the expected "it's a great waste of your time, your techinque is more important than your pellet/velocity combo, etc., etc." My point is if you have some time to do this testing, you can step up on the line knowing that you have the best possible combo in your hand, and I believe that helps with confidence. And, we could all use a little more of that!
Stan
Understanding that the factory test target doesn't tell us much, it makes me wonder if one shouldn't spend an hour or two to find the right combo for your pistol or rifle. In additon, I was cleaning out some files today and found my pellet tests for my old FWB Mdl 2 and C20. The results were shocking.
In short, I tested both of those pistols with multiple pellets and multiple velocity settings. For the Mdl 2, I found a pellet and velocity combo that shot groups that really looked like a single pellet. With the C20, I never quite got as good a result, even though it had the separate chamber and should have been less resistant to temp changes. It is important to say that with other pellets and especially with different velocity settings, the results were much worse. Some were so bad, I would have returned the pistol for repair.
The point of this is that I've never touched the velocity setting on my Morini APs. I kind of wish I had done so now. How do I know that the factory has it set for the optimum velocity for the pellets I'm using? I don't.
Please don't deluge me with the expected "it's a great waste of your time, your techinque is more important than your pellet/velocity combo, etc., etc." My point is if you have some time to do this testing, you can step up on the line knowing that you have the best possible combo in your hand, and I believe that helps with confidence. And, we could all use a little more of that!
Stan
-
Guest
We ( a friend and myself ) made a set of "jaws" to fit in a vise and hold tight around the air cylinder. It worked quite well actually, as we both had experience with Ransom Rests. We tried 4 different brands of pellets and a total of 3 different diameters as I recall. Quite honestly it really did not make any noticiable difference that either of us could see. He used his LP2 and I used an LP10. I guess if you had some real cheap pellets it may show up, but we tried Vogels, Walthers, JBS, H&N and got about the same results from them all. This is just my (our) experience, you may have found out differently.
To echo Scott,
I just dragged out the chrono and my Morini 162:
RWS R10 .5g (head diameter not matched to gun):
50 shots avg vel 458.6fps std dev 3.3fps extreme spread 13fps
RWS MK .5g :
50 shots avg vel 454.2fps std dev 5.1fps extreme spread 18fps
RWS Hobby .45g:
50 shots avg vel 474.9fps std dev 6.2fps extreme spread 20fps
I didn't fire groups, but would think that unless there were extreme cases were the pellets' shape was somehow wildly nonconcentric, they would not group significantly different. In practice, they shoot the same size group and point of impact. At 10 meters, it really is a statistical wash. The difference is price per tin: $5 for Hobby, $7.50 for MK and 10$ for R10s. For me it will be the cheaper pellet for practice, league matches, and PTOs, and save the good stuff for State level matches and above. Of course your philosophy and mileage may very.
cricman
I just dragged out the chrono and my Morini 162:
RWS R10 .5g (head diameter not matched to gun):
50 shots avg vel 458.6fps std dev 3.3fps extreme spread 13fps
RWS MK .5g :
50 shots avg vel 454.2fps std dev 5.1fps extreme spread 18fps
RWS Hobby .45g:
50 shots avg vel 474.9fps std dev 6.2fps extreme spread 20fps
I didn't fire groups, but would think that unless there were extreme cases were the pellets' shape was somehow wildly nonconcentric, they would not group significantly different. In practice, they shoot the same size group and point of impact. At 10 meters, it really is a statistical wash. The difference is price per tin: $5 for Hobby, $7.50 for MK and 10$ for R10s. For me it will be the cheaper pellet for practice, league matches, and PTOs, and save the good stuff for State level matches and above. Of course your philosophy and mileage may very.
cricman
-
Neil Foster
- Posts: 107
- Joined: Sun Oct 31, 2004 1:57 pm
- Location: Marietta, GA
-
Richard Newman
Pellet testing
Head diameter is probably only part of the question. Each pellet has a skirt, which will deform to some degree, and engage the rifling of the barrel. Whether that deformation is uniform around the circumference, and if it is the same amount shot to shot (affecting pressure, velocity and maybe stability) need to be considered. I haven't looked at my pellets under a scratch guage to measure the rifling impression - which is probably very small - but I suspect that some pellets will show little or no engraving on the head, and possibly uneven engraving. This would indicate some asymmetry and possibly is a better indication of potential accuracy. How fast does a pellet rotate on leaving the typical air pistol barrel? Has anyone measured this? It could have some bearing (pun intended) on accuracy.
Richard Newman
Richard Newman
Great info, look forward to testing article
Good info which I have passed on to those who look at me sideways when I tell them pellet/gun evaluation is just like 22 ammo evaluation. They are stunned.
Anywho, I have up until now never fooled with finding the optimal diamter for my 10m gun. My focus was toward youth programs and ensuring what they had was suitable and affordable for the duration. That means i have a wide range of rifles to bench and as such, I have opted not to build a vice. Plus, for those in the cheap seats still shooting FWB 300S and SSP, building a vice, well, was more work than I wanted.
So. I put on a Sightron 6-24 that focused down to 10m and tested off a bench. Having just skimmed The Ways of the Rifle, I again see the need for a vice to match pellet & rifle. Hummm? How to test without a vice?
Pls comment on how to vice a SSP or Lever Spring gun. Here was my results just testing brands so I could figure out what to use for the kids...with my SSP thrown in as a control. Kind of embarasing! I concluded that the 5,000 of Chinese mfg Daisy pellets from CMP was a poor use of club funds and used them for those just trying to hit the black. Argh! Vogels NEXT time!
http://i105.photobucket.com/albums/m205 ... pellet.jpg
Anywho, I have up until now never fooled with finding the optimal diamter for my 10m gun. My focus was toward youth programs and ensuring what they had was suitable and affordable for the duration. That means i have a wide range of rifles to bench and as such, I have opted not to build a vice. Plus, for those in the cheap seats still shooting FWB 300S and SSP, building a vice, well, was more work than I wanted.
So. I put on a Sightron 6-24 that focused down to 10m and tested off a bench. Having just skimmed The Ways of the Rifle, I again see the need for a vice to match pellet & rifle. Hummm? How to test without a vice?
Pls comment on how to vice a SSP or Lever Spring gun. Here was my results just testing brands so I could figure out what to use for the kids...with my SSP thrown in as a control. Kind of embarasing! I concluded that the 5,000 of Chinese mfg Daisy pellets from CMP was a poor use of club funds and used them for those just trying to hit the black. Argh! Vogels NEXT time!
http://i105.photobucket.com/albums/m205 ... pellet.jpg
I don't know if they still make them, but I use a Black & Decker Shopmate, a folding table type vice. I have a 1"x1"x8" block that I can attach to a gun rail with the Daisy 888 sling handstops .... I removed the thumbscrew and installed a short section of (I think) 1/8" all thread and have some wingnuts to tighten it up. Clamp that in the vice, and if necessary weight it down with sandbags or shotbags. I can use it on a wide variety of air and smallbore riflesI again see the need for a vice to match pellet & rifle. Hummm? How to test without a vice?
So true ... the Crossman copperheads are OK, but the cheap Walmart (Crosman) pellets are the same as those Chinese pellets .... absolutely terrible ... I have a very small stock that I use only on the first day shooters that I let shoot off a bench into a pistol target ... there are so many very good pellets in the $5-$9/tin range why bother with the garbage.I concluded that the 5,000 of Chinese mfg Daisy pellets from CMP was a poor use of club funds and used them for those just trying to hit the black. Argh! Vogels NEXT time!
I really like the samples of the USA Vogels that Scott handed out at 3X Air ... they were very good, even in the precision guns. He's on the right track
-
Fortitudo Dei
- Posts: 256
- Joined: Tue Mar 02, 2004 8:30 pm
- Location: New Zealand
What I'd really like to see would be sample pack made up of (say) 50 pellets of each sized pellet made making a total of 250 pellets. I know they would be fiddly to put together and each group of 50 would have to be bagged separately, but I would be happy to pay a premium price for such a product so I could pellet test without having to buy 5 x 500 pellet tins.