Should I sort pellets by weight or head size? Or both?

"Paio"A) Head diameter?
B) Skirt diameter?
C) Weight?

What is really the most important and the one I should concentrate my efforts and time?

8 - I visited JSB internet site and noticed they have premium pellets on .177 calibers ("individually selected pellets only from the best manufacturing batches" and certainly for competition). I wonder why not they don't have for other formats and calibers. Certainly there is a market for that.

Last but not least, I also do plinking and hunting. For these I only sort pellets by visual inspection. My quest in sorting pellets in a more technical way are for long distances shots such as 100m and above at my range. I just want to tighten my groups and be a better airgun shooter. Thanks.

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The first question you have to ask yourself is what is your acceptable level of accuracy? I shoot benchrest at 25m, 50y, 75y and 100m. At 25m and 50y I need/want to be able to place a pellet dead center of the bull plus or minus 0.1" at 25m and plus or minus about 0.2" at 50y and do that 75 times in a row without a flyer. At 75y and 100m I need/want to shoot 1/2 MOA to 3/4 MOA and need to be able to do that 60+ times in a row.

Head size IME makes the most difference, skirt size and weight are of MUCH less concern. Having things consistent is more important than anything else. Through trial and error find the head size that your gun loves and then buy or resize to that head size. If the skirt is round and doesn't flop around in the chamber its good enough. Weigh pellets into groups, the spread of groups will be based on how your guns deals with it.

Example with my Thomas at 25y, the difference in elevation between a 13.0gr and a 16.2gr pellet is about 1/2". The difference between a 16.0gr and a 16.2gr pellet is so small I can't measure it. But that doesn't mean there isn't a difference, just that its too small for me to measure with the setup I have.

There is a unknown factor IME that we are missing in pellet selection. I suspect its that not all pellets have there center of gravity centered in the pellet. In the image below look at the flyer between bulls #11 and #12, the POA for that shot was the #7 bull! I sorted (100) pellets, I weighed them into a group of 16.0gr to 16.2gr, I resized them to 4.53mm, I visually inspected them under magnification. Yet I get this flyer. I shoot in reverse numerical order, so I shot #7 the flyer, then #6 also what I would consider a flyer albeit at a much lessor amount, I came and reshot #7 after finishing the card (never leave a blank bull!). 



The reason JSB doesn't do the "hand selected match grade" thing for anything other than 0.177 is the 10m shooting crowd is driving that, remember that 10m is a Olympic sport with nations backing teams where gold medals are worth a lot to all involved. If/when the benchrest shooting is part of the Olympics then you will see manufactures "hand selecting" pellets for all calibers, till then, we are just the mass market and the only voice we have is our spending power, which with lack of choices is kind of mute. They are turning out pellets as fast as they can and there are still often shortages, which tells them what they are doing is just fine, no need to change.

Thanks for the links Percula,

I started looking into that option after posting yesterday and have already ordered this adjustable one from TR Robb so I'll see how that goes:
http://www.trrobb.com/product/adjustable%20pellet%20sizer%20177

Do you find that it makes any difference how much you are resizing a pellet by? 

Asa, your shooting results are very interesting. I read this twice, but to clarify for me, you sorted into the group sizes shown from the various tins, and then shot from measured groups, correct?

It is great to see some validation with such a significant number of controlled shots. Thank you!

There was a review with some testing published on a UK website related to field target, called Pellet on Pellet. In this test, a tin of JSB 8.4 grain .177 pellets was sorted by head size:
4.49=0.59%
4.50=15.98%
4.51=51.48%
4.52=27.22%
4.53=2.96%
4.55=1.78%
You'd have to wonder whether the 4.49 or the 4.55 would likely be fliers.

"Pelletgage"Asa, your shooting results are very interesting. I read this twice, but to clarify for me, you sorted into the group sizes shown from the various tins, and then shot from measured groups, correct?

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Yes that's correct, I had a fair few tins by the end... and each one had pellets of one particular head size from a particular original tin ie: I did not mix pellets from different original tins even if they were the same (published) weight and head size.

But there are definitely some gaps that I would like to fill ie: is a 5.52mm 18gr same/better than the 16gr 5.52mm, and what happens with my barrel below 5.52mm? Will other pellets types resized to the optimum head size for a given barrel work as well? I suppose what the next quesiton would be is: HOW significant is the head size over every other factor for our "pellet fussy" airgun barrels?

"Asa-J"Thanks for the links Percula,

I started looking into that option after posting yesterday and have already ordered this adjustable one from TR Robb so I'll see how that goes:
http://www.trrobb.com/product/adjustable%20pellet%20sizer%20177

Do you find that it makes any difference how much you are resizing a pellet by? 

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The only "fussy" that I've had resizing has been with slugs for my 30cal. Resizing the JSB pellets results in no measurable rebound, same with H&N pellets. Resizing cast slugs has resulted in little to significant rebound. The starting head size is fairly consistent with the JSB. But if I get one that falls too far into the die or is too hard to push through, I toss them. With the tBt and NOE when you drop the pellet in, you will soon begin to see "too large" or "too small" by how deep or shallow they fall into the die.

I really wish NOE would make a 0.177 insert in a 4.53mm, but so far nope. I love their 30cal sizer, I can whip out a tin (150) 30cal in less than 20 minutes. 

"Pelletgage"There was a review with some testing published on a UK website related to field target, called Pellet on Pellet. In this test, a tin of JSB 8.4 grain .177 pellets was sorted by head size:
4.49=0.59%
4.50=15.98%
4.51=51.48%
4.52=27.22%
4.53=2.96%
4.55=1.78%
You'd have to wonder whether the 4.49 or the 4.55 would likely be fliers.

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He makes a good point in that review, and something I had thought in the defence of the pellet manufacturer, pointing out that to make something to 0.01mm that we are talking about here out of soft lead is a pretty big ask... but then why sell them in gradations of 0.01mm when, as we see in his test and in mine, the majority of pellets may fall well outside of the published size? 

As to whether the extreme sizes would necssarily be fliers, I think that probably depends on the individual barrel. Off the top of my head I can think of one manufacturer who makes a pellet in a 4.48mm / 5.48mm head size option... (assuming that is how they turn out of course) whcih is Pax Guns and their Defiant range.

"Percula"
T But if I get one that falls too far into the die or is too hard to push through, I toss them. With the tBt and NOE when you drop the pellet in, you will soon begin to see "too large" or "too small" by how deep or shallow they fall into the die.

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That makes sense, thanks.

A gentleman named Cliff Tharp formerly published a BLOG called "Varmintair" where he discussed his avid pursuit of prairie dogs and other "varmints" with his airguns. Cliff achieved amazing results, and his rifles were absolutely capable of sub MOA accuracy in long range (out to 100 yds) shots on his hunts. Cliff was an early adopter of Pelletgage. He published several very useful articles about pellets and pellet sorting. Unfortunately, the BLOG is now inactive, I regret to hear Cliff had serious health problems. His expertise and great writing will be missed - but I did find a web archive which allows historic posts to be accessed. It's very relevant to this discussion. 
https://web.archive.org/web/20160517152841/http://varmintair.typepad.com/varmintairs_blog/pellets/

"fe7565"

"Paio"

2 - I badly want to resize all pellets skirts to single diameter to improve the rolling method accuracy and I couldn't find anything which I really trust. What I found are pellets head sizers (like this one well made here: http://www.airrifletuning.com/products/tbt-pellet-sizers/). These ones will resize the head and skirts to a same diameter which it does not make any sense for me. Please correct me if I am wrong here. Does anyone know any device that resizes the pellet head and skirts simultaneously in different diameters?

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http://www.trrobb.com/product/adjustable%20pellet%20sizer%20177 This one leaves the skirt intact and may even straighten it a bit.

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I have one of those Robb sizers in .177 for sale. Used just a little and works as described.
Joe Peacock

"Pelletgage"A gentleman named Cliff Tharp formerly published a BLOG called "Varmintair" where he discussed his avid pursuit of prairie dogs and other "varmints" with his airguns. Cliff achieved amazing results, and his rifles were absolutely capable of sub MOA accuracy in long range (out to 100 yds) shots on his hunts. Cliff was an early adopter of Pelletgage. He published several very useful articles about pellets and pellet sorting. Unfortunately, the BLOG is now inactive, I regret to hear Cliff had serious health problems. His expertise and great writing will be missed - but I did find a web archive which allows historic posts to be accessed. It's very relevant to this discussion. 
https://web.archive.org/web/20160517152841/http://varmintair.typepad.com/varmintairs_blog/pellets/

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Thanks for that Pelletgage, I remember a blog a few years ago with incredible video of long range prairie dog shooting - it totally inspired me - and I was dissappointed when it went offline, sounds like it may have been the same one.

Just checked out the blog via the link and it is awesome, great info re this topic, in fact he pretty much puts it to bed... this guy is a master! Very sad to hear he has health problems.

I've been doing both lately and I believe that the practice does reduce the number of fliers when I'm shooting my .177 R9, however I can't prove it decisively with my shooting skills.

For pellet head sizing I use a home made sizing die and ram that rounds and slightly flared the pellet skirt as it swages the head. I does take me about 5 seconds per pellet to size them but I do this chore while watching YouTube airgun and machining videos. After a couple low stress hours I have a 1250 count box of CPLs all uniformly sized to a 4.52ish mm.

A few weeks ago I started sorting my CPLs by weight into three groups, 7.90gr-7.98gr..........8.00gr-8.04gr...........8.06gr-8.12gr
The few pellets that are under 7.90gr and over 8.12gr are tossed out.
First I calibrate my scale.........


Then the weighing is done same as the sizing, while watching YouTube airgun and machining videos. Here is the result after a few evenings.........


Personally I believe that actual pellet head size isn't very important as long as all pellets are large enough to be swaged a bit when loading into the leade (i.e. a snug fit). When all pellet heads are reduced simply by pushing into the leade they will be a consistent size determined by the leade itself. The issue comes when pellet heads vary enough that some pellets are "loose fitters" that don't get swaged and other pellets are "snug fitters" that do get swaged. 

I'm coming to the conclusion however that extremes in pellet weight do affect the poi at longer distances and I am getting some positive feedback by shooting only one "weight sort group" at a time and that group is the one weighing 8.00gr-8.04gr which just happens to be the most prevalent size from my sort of CPLs that are advertised as 7.9gr.

You are correct. But what did he do of his gun? I though he was going to make a video about it. Do you now where else he posts?

I personally refuse to defend the manufacturers ! If you are advertising that your product is a certain size, then at least most of the pellets in that container should be that size ! We too easily accept this type of thing way to often anymore. Good thing we have the pelletgage, dies and digital scales. pelletgage tks for the link to the archived information. Very informative and enjoyable to read. Too bad he is unable to continue.

After measuring thousands of .177 JSB Exacts and H&N FTTs I do tend to agree with your statement except I believe there should be no stated sizes on the tins. LOL....I found numerous pellets from an Exact labelled 4.50 size tin that were larger than the pellets from an Exact labelled 4.52 size tin and visa-versa, same for the H&N FTT. I've never cared to try them due to price but SUPPOSEDLY hand sorted JSB Exact Premium pellets are exactly what you want for about $15 per 200 count box!
http://www.pyramydair.com/s/p/JSB_Exact_Premium_Diabolo_177_Cal_8_44_Grains_Domed_200ct/1267

Anywhoo.....I never realized how precise a measurement of 4.52mm was until I started making my own pellet head sizer. For the last couple days I've been making up a new pellet sizer specifically for sizing CPLs for use with my .177 HW95 which has a tighter leade than my .177 R9. When machining the "D" reamer for reaming the sizing die I deliberately machine my cutter for reaming a 4.46mm sizing ring in the die, then the die is hardened, then lapped till the sizing ring was 4.49mm. Well...the difference between 4.46mm and 4.48mm is only "some grey coloring" on the rolled and rolled 500 grit wet or dry abrasive! I just finished my second sizer because the lapping of my previous die gave me a pellet head of 4.51mm instead of 4.49mm.

My personal belief is that as long as the pellet head is swaged a bit when loading it really doesn't matter what the "second metric decimal" is because all pellets will be swaged to the same bore size when shot. The issue is those all too frequent undersized pellets from some tins (regardless of the size markings) that don't engage the leade snuggly. I know from experience with my .177 R9 that if a pellet fits "noticeably loose" in the leade it will be a flier. To put things into perspective, the difference between 4.50mm and 4.51mm is only 0.0003937008in which is less that 4/10,000th of an inch.

As far as pellet gages are concerned, I really don't see how they help unless the pellets are wildly out of spec because they only size the widest part of an oval and I've found that many pellet heads are actually oval by as much as .01-.02mm. There are those using "holes in a plate" that have posted positive results which is puzzling to me. As I mentioned previously, as long as the pellet head is swaged a bit when loading into the leade, it really doesn't matter if the pellet head is off a few hundredths of a mm.

Concerning pellet weight variation, this may have more impact of the pellet trajectory than the pellet head being off a few 1/100mm (assuming a good fit in the leade). One of the features of the 7.9 grain CPLs from the die lot marked and dated 1250 count box is the fact that their heads are larger than most at about 4.54mm-4.55mm (why they tend to fit tight in most leades) so they almost always fit the leade of my HW springers snugly. Matter of fact, the heads of almost all CPLs are sized when pushed into my 4.52mm pellet sizer. LOL...tried that with JSB Exacts and almost all pellet heads weren't sized at all in my sizer. Anywhoo, back to pellet weight..........I sorted my CPLs into three weight groups 7.90-7.98grains, 8.00-8.04grains and 8.06-8.12grains. After weighing and sorting 4 boxes of CPLs (5000ish pellets) I ended up with a bit over 100 pellets total that weighed less than 7.90 or more than 8.12grains and they were all tossed out. The remaining pellets from all those CPLs weighed less that 1/10th grain from "light to heavy." Matter of fact, even the span from the lightest tossed CPLs at 7.84grains and the heaviest tossed CPL at 8.20grains variation was less than 1/2 grain. As a side note, most tossed CPLs weighed 7.88 grains.


Bottom line.....Perhaps a good PCP shooter could tell the difference in accuracy between pellets weighing about 1/2 grain apart, however with these mixed weight die "B" CPLs sized to 4.52mm and lubed with Slick50 OneLube I couldn't tell any difference in accuracy with my shooting skills.

Anywhoo......I'm fond of CPLs simply because their larger head size will almost always be sized in the leade when loading and their weights are extremely consistent. The reason I size my CPL heads is simply because they are "sore finger loading" for my tight leade HW95, however unsized they work perfectly in my R9. I found that if I sized the CPL heads to 4.52mm they shoot well from both my HW95 and R9, however 4.52mm is still a bit tight for the HW95 so I needed to use a pellet seater so I didn't get an occasional deformed pellet skirt when re-latching the barrel. Here is a deformed pellet skirt after relatching my HW95 barrel.........

I'm pretty sure that pellets from my newly fabricated 4.49mm pellet sizer will "finger load" easily and still be swaged a bit in the leade, however if not I can still open up the sizing ring by lapping to 4.50mm. 

Ed I have that same scale, works great. Still being a newb, I was wondering just how anal do I need to get ? For the newb who is new to shooting anything all this can get to be a bit over whelming. For me not so much, lots of experience with sizing/weighing bp projectiles and others. I would think your variables would change according to pellet weights. IE: it would be narrower with a 7gn pellet than it would be with a 10gn pellet. I would also think that how anal you are about the size would change depending on manufacturers and materials used. My .22 cal likes copper pellets, since they are harder and will not expand as easily as a lead pellet. Should I be more anal about them ? I know the cpl pellets are harder than others. Soon as I get moved into my house and get target range setup, I am going to try a field test, put chrony at 10 then 50 yards and compare the fps difference in say .177 in 4.48 - 4.53 and see what variances more drag has in fps and accuracy at longer range. To me it would seem if you say have 4.51, 4.52 and 4.53 all grouping good, then the 4.53 should show a lower "poi" due to more drag. This is why I think sizing is just as important as weighing. I am working on shooting FT and I want to squeeze every bit of accuracy out of my rifle I can, then its my fault when I compete and my buddies there at THAGC bust my chops a bit, which I do deserve as much grief as I give Jimmy and Dwight

Ed, I guess you have never had a tin of pellets sort like this one:

You disparage Pelletgage as "holes in a plate", but I think it is the simplest and most positive way to determine if a pellet exceeds a precise round opening (gaging, not measuring). Measurement with calipers is really only measuring one chord. Dropping the pellet through a perfectly round, precise cylindrical opening in a stainless steel gage plate is the Pelletgage concept.

If pellets are really ovoid, and consistently exceed the diameter you desire, they are more apt to shoot poorly. I contend an ovoid pellet would likely not have good ballistics, and would fail the Yrrah method. Usually, I find the majority of gaged tins to have 95% or more of the pellets within 0.01 mm of the mean size. When a tin of pellets with significantly higher variance is found, they do NOT shoot as well. I have also seen two tins of pellets with a mean shifting by 0.02 mm, and yet both tins are quite consistent. In such cases, they may group well, but I believe there will be a POI shift.

But the bottom line is that pellet manufacturers are shipping product that is imperfect, sometimes grossly. Several of my customers have sent me images and descriptions like the one pictured - and the guy who did the one pictured is a process engineer who works in a high precision industry. That one tin had 4.47 to 4.53. He said the shooting results were highly correlated with the most variant pellets. Cavet - I still think the JSB Exact is a great pellet, and this is atypical. Other well known brands have shipped tins with the even more variance. 

I generally agree that 0.01 mm shift in head diameter is not significant. 

My recommendation is to all seeking the "liked" pellet - first sort out enough pellets of a type you have, in order to get some batches that are 0.01 mm apart, and shoot ten shot groups from each batch to find the head diameter that groups best for your rifle. Then, when buying pellets, sample 10% or more from a new tin. Calculate the mean of your sample. Not more than one pellet should exceed 0.01 mm from that mean - two sigma variance is the goal (95% within +/- 0.01). The sample mean should be no more than 0.02 mm different than your desired size. Now, if you are shooting a match, the half hour that it may take to sort every pellet you'd need for the match might still prevent one flyer. 

I always find that gaging the first 50 or so tells me everything needed about that tin of pellets.