TargetTalk

Perhaps a bit of a dumb question, many of mine turn out that way it seems.....but,

I’ve been browsing around the various pellet makers web sites and can’t seem to find out how the different makers arrive at the weights of pellets they make.

The weights just seem so arbitrary. 7.02, 7.33, 7.87, 8.02, and so forth.

Why not in steps, like 7, 7.5, 8.0, 8.5, etc. Or in less broad steps in weight. Whatever. Different skirt sizes I can see due to variations between barrel makers.

On the new Eley Ventus pellets for instance, Eley says they determined 8.02 to be the optimum weight for air pistols and air rifles. How? They were able to see a difference between 8.02 and 8.0?

Do they just have a broad sampling of the top air guns clamped into ransom rest type devices inside a test tunnel?

Re Ely pellets - Marketing BS. There cannot be an optimum weight for all pistols- let alone pistols and rifles.

Having a range of shapes and weights lets you select the most stable for your weapon. Half a grain is maybe too wide a step if they all adhered to such a standard

TenMetrePeter wrote:Re Ely pellets - Marketing BS. There cannot be an optimum weight for all pistols- let alone pistols and rifles.

Having a range of shapes and weights lets you select the most stable for your weapon. Half a grain is maybe too wide a step if they all adhered to such a standard

I agree. Dunno how the can say it’s optimum. That’s a pretty broad brush.

I agree you’re right that half a grain differences may be too much, I just used that as an example. The weights just seem to be odd to me. 7.33, 8.02, strange, but I imagine somewhere someone decided that’s a good weight to go with. Maybe they test in .01 increments?

Oh groan! Pellet weights and accuracy are linked very tightly and are very difficult to get right!!!

PELLET WEIGHTS

How do vendors give you a weight on the can? Count 500 pellets (or a thousand or 10,000) weight all at the same time on a hopefully accurate balance and divide by the number counted. Average is the "can weight." Pellets are made in dies that stamp out zillions. The dies are made to deliver a certain mass of lead (or whatever the blend is.) Each die may deliver a tiny bit different amount because of wear or manufacturing tolerances, providing a range of weights that go into each can. Pellets from different dies are frequently mixed together from different dies.

Sometimes, the variation can be considerable, especially out of tins bought at retail or from an on-line vendor. Example: I weighed Kodiak Match pellets purported to be 10.56gr. The 200 or so that I weighed and separated into batches for testing ranged from 10.2 to 10.6 with a tin average of 10.39. When I shot them from each separated group, I had a small but noticable vertical stringing result. Lighter pellets hit higher than heavy pellets. Gravity works that way.

A second batch (not Kodiak and I don't remember which it was!) had two distinct populations of weights in the same can. One around 8.2 gr and the other around 8.6 gr.

Many serious competitive air gun shooters will buy large lots of pellets bulk packed from a single die in hopes of better consistency. It works for them.

SCALE AND BALANCE ACCURACY:

The MOST important problem with weighing pellets is the accuracy of the your scale or balance. Most people who weigh pellets use powder balances or scales from the reloading bench. These can generally read to 0.1gr. That does not mean it is accurate to 0.1 gr, that means it can DISPLAY weights to 0.1gr. In powder shooting this is generally OK as bullets and powder charges can range from around 40gr to 250gr or so. That means the error is small. In pistol ammunition reloading this is not good enough as powder charges as low as 3gr are fairly common. That means an error of 0.1gr is 3% of the charge - assuming the scale or balance is accurate to that weight in the first place. Personally, I throw at least 10 charges and take the average.

I have an old Lyman-Ohaus powder balance that has served me well for many years. I have a MTM powder scale that is so-so. I recently bought a GEM scale. The Ohaus and MTM display to 0.1gr. The GEM scale displays to 0.01gr. I have a set of analytical weights traceable to the U. S. Bureau of Standards, now part of the DOE. They were used in my laboratory years ago. I weighed each of the standard weights on the 3 scales/balance noted and plotted their linearity and accuracy to the calculated grain weight of the analytical weights. They were all accurate to a low weight of 1.0gr. Below that not so good. I also checked repeatability by weighing the same pellet 10-20times. At 10.5gr nominal weight, I got a range of 10.3 to 10.8gr.

I separated 100 pellets from the same tin into batches 10.2-10.29, 10.3-10.39, etc up to 10.5-10.59. I shot them into groups - vertical stringing - a little at 50' range not significant in my accuracy range. BUT when I weighed each batch together. That is all those in the 10.2-10.29 batch and so on. Each batch weighed an average of 10.39gr!!! (The actual tin average.) All my separation was testing the scale, not the pellets!

This led me to buy the GEM scale (used in the jewelry trade to weigh gem stones that displays to 0.01gr I redid some of the experiments noted above, I got results that I would trust to about 0.02gr. That means, I can sort to 0.1gr confidently. If I wanted to get really picky, I would buy a used analytical balance capable of accurately weighing to 0.0001gm or 0.001gr. I see them on evil bay occasionally.

WHAT'S WRONG?

The Lyman uses agate knives for low friction contacts between the balance beam and the base. The Lyman is a true balance that is, it compared weights on a balance beam to weight in a pan. This is ultimately the most accurate way to obtain weights of anything and is the method upon which our weights and measures system is based. However at very low weights of a couple grains the Lyman balance isn't really sensitive enough.

The MTM Powder Scale and the GEM scale are both electronic strain gauges (or load cells if you prefer) that must be calibrated against a known weight. Each scale comes with such a standard weight that are generally in the 100gr+ range and give one point on the line. The strain gauges are calibrated for linearity across a useful range (say 5 - 1000gr) but at the ends of the range, accuracy suffers. Visualize a teeter-totter. The pivot point in the center is the calibration weight. If the linearity is good and the strain gauge is calibrated to the "correct" slope the weights you get are quite good enough. BUT incorrect slope setting can be a nasty problem. The first one of the electronic scales I bought, also from MTM, seemed great when I got it but I noticed that powder volume in a couple 30/06 cases seemed different than I remembered from past work. I weighed the powder with the Lyman and found them to be over 5gr light. That was actually good news as 5gr heavy would have blown the primer clear out of the case and damaged the gun and me!!! MTM people said "oh, throw it away and we'll send you a new one. We've had a about 5% of this batch that were bad."

Advice: Unless you shoot at near Olympic levels it probably isn't necessary to weigh and sort pellets. If you are at that level, you probably know all this anyway! Buy good quality pellets, shoot for group out of the tin, select your pellet type for the shooting you wish to do and get on with it. If you find a tin that really does well see if you can find more from that lot. Ultimately, you may want to buy the bulk pellets attributed to a single die but that gets complicated.

dtdtdtdt wrote:Lighter pellets hit higher than heavy pellets. Gravity works that way.

Sorry, that just rubbed me the wrong way so I had to respond. Should read:

FASTER pellets hit higher than SLOWER pellets. Gravity works that way.

Gravity pulls on slower pellets before the target longer than faster pellets. Everything else being the same, heavier pellets are slower than lighter pellets. Pressure, force, and acceleration work that way.

I don't disagree with the point you make and have seen it multiple times at longer distances. However, pellet velocity differences between 10.2 and 10.4gr are very small probably in the 5f/s difference range. The vertical stringing that I saw was about 1/4" at 50' and 860-65f/s. The stringing was definitely biased toward the heavier pellet weight as I knew which one I was shooting and watching through my scope. I was quite surprised to see the effect at the short distance anyway.

In another set of tests I did, I shot pellets ranging from 4.5gr to about 13 gr for accuracy and recorded point of impact. At 50' the 4.5gr pellet hit about 3" HIGHER than my normal 10.5gr pellet. Velocity was 1197f/s versus 865f/s. Incidentally, the 4.5gr non-lead pellet shot a 4" group versus the 10.5gr pellet 0.4" group all under same conditions, same day, same gun, same cranky old so&so behind the trigger.

To avoid snarling, let's just agree to disagree. We both know we are right! GRIN!!!

dtdtdtdt wrote:To avoid snarling, let's just agree to disagree. We both know we are right! GRIN!!!

If you want. But now I'm not quite sure how you think air resistance will be greater for the heavier pellet. Heavy or light, they're the same basic shape, same cross section, probably identical or close coefficients of drag, and should have similar resistance.

The heavier pellet would be affected less than a light pellet for the same air resistance force. The faster pellet to leave the barrel will experience the higher air resistance force.

Now, to make that discussion moot. Whether slower leaving the barrel, or slowed more by air resistance, the slower pellet on average is affected by gravity longer and will drop further.

In the absence of measured experimental results, I resorted to Hawke ChairGun Pro for the calculated values.

The calculated results show that the weight range of 10.2 to 10.5gr had no different drop.
A velocity range of 840 to 880f/s had an increased drop of 0.05" for the higher velocities.
You are right! I am wrong. My observation of increased drop must have been me being sloppy.


The rifle is zeroed for 30yds with my pellets. Shooting at 50' indoors. The range of weighed pellets was 10.2 to 10.5 with an overall average of 10.39gr. Measured velocities: 840-880 f/s with average of 865f/s

Pellet: Kodiak Match 0.177",
Tin Weight: 10.65gr,
Calculated Ballistic Coefficient: 0.0240
Sight Height 1.50"
Far Zero 30yds
inclination 0
Wind None
Temp 68F,
Air Pressure 972mB
Elevation (my backyard!) 955'above mean sea level
50% Rel Hum

Target Distance 17yds.


Actual Pellet Weight Muzzle Velocity Measured POI distance from POA

10.2 gr 840f/s -0.01"
10.2 gr 860f/s -0.03"
10.2 gr 880f/s (simulated) -0.06"
10.5 gr 840f/s -0.01"
10.5 gr 860f/s -0.03"
10.5 gr 880f/s -0.06"

Just for fun:

10.4gr pellet range 840 to 880f/s muzzle vel. Target 50yds

840f/s -2.27"
880f/s - 2.02"

10.6gr

840f/s -2.27"
880f/s -2.02

Regarding the velocity versus weight and drop. Granted these are thought experiments using a program and stretching it to ridiculous levels! It shows that if energy is held constant the POI is essentially identical for the range of pellet weights and velocities used. In this case, it computes to 16.9 fpe for the actual pellets tested.

Computing the projected velocity using the known weight and energy one gets these velocities and projected drops. None of the differences are material. At 17yds, the higher velocity, lighter pellet dropped 0.02" less. At 50yds the heavier, slower pellet dropped 0.07" more. Obviously, weighing pellets and selecting a narrow range AND ensuring that your rifle delivers a very consistent amount of energy to the pellet will give even smaller variations than I have seen and that these calculations predict. BUT for the average shooter it says, don't waste your time. Work on your position and trigger pull instead!!

10.2 gr pellet, 865f/s, 16.9fpe 17yd drop: +0.07" 50yd drop: -2.28"
10.5 gr pellet, 852f/s, 16.9fpe 17yd drop: +0.09" 50yd drop: -2.35"

Tin Average Pellet;
10.39gr, 856f/s, 16.9fpe 17yd drop: +0.08" 50yd drop: -2.33"

At the range with a near zero at 17yds and a far zero of 44yds, the calculated drop showed -1.08" at 50yds versus a measured -1" when shot. 2 Groups 5 shots 0.9" AND 1.1" edge-to-edge.

This says that within reason, weighing and separating pellets is a waste of time AT MY LEVEL OF SHOOTING. However, this discussion has been very valuable to me. THANKS!

Love dtdt's response. Never mind if there is a technical niggle on heavier versus faster, at the end of the day, I think he nailed several things:

Pellets are made in multiple molds, that is multiple pellet molds are operating side by side, and the output stream in not segregated such that 1 mold feeds a tin, rather they are all mixed, so as the molds wear, or get pulled out of service for cleaning, the average weight is always swinging a little. I would not be at all surprised if they start with a shape they like, make 100 or 1,000 molds to that shape, then weigh the average. So the weight is the result of the design, rather than starting with a final weight and figuring out how to make a pullet out of it.

ShootingSight wrote:...
Pellets are made in multiple molds, that is multiple pellet molds are operating side by side,....

Pellets tend to be rapidly stamped in dies from lead wire from reels rather than cast in moulds (excuse British spellings) so there's not as much duplication as with moulding your own bullets in a row. However banging them out at 5 or 10 per second does take its toll on dies which need to be replaced. You then have a whole batch slightly different and probably several machines (at H&N 30 machines) running side by side.
https://www.youtube.com/watch?v=22z4W4cGX7k
I wrote to the famous german company who produced the factory video suggesting they banged them out then sorted them into sizes but they were horrified and insisted they made them as 4.50 then made another batch at 4.51 etc. I don't believe them! The second video shows them "buffered into lots" which to me suggest size sorting.
They also had a lady who visually checked a whole tray of several thousand at a time. She was apparently genuinely capable of spotting a bad one at that rate.

To be precise, I said dies. I didn't imply or say that they were moulding them from liquid lead like a shooter would do at home.

Wear, manufacturing variation, and processing speed have a lot to do with lot-to-lot variation. Every manufactured product has variation in their properties.

Part of my discourse here was to point out that the measurement tools, in this case scales and balances, also have tolerances and variation. A $100 scale or balance cannot compete for accuracy with a $5000 analytical balance. (I happen to own a very old and very accurate 2 pan analytical balance that is older than I am (71!) it is still capable do accurately discerning the weight of the ink on a piece of paper. I did it once with a post-it-note and a sentence written on it just to see if it was that good! I even know how to use it after all these years. I didn't use it for this as it is a real pain to set up for that level of accuracy and didn't think I needed to do so.

Incidentally, the video showed them weighing individual pellets with a modern analytical balance as I hope I would see. That's the $1000 or higher solution.

I visualize Helga Eagle Eye sitting on a stool overlooking the the millions of pellets zooming by and she reaches out to snatch the really bad one. ; Perhaps she should snatch the best ones for me????? What if she sneezes, yawns, or runs to the potty???? A zillion unviewed pellets go out!

Also reminds me of a Honda lawnmower commercial with Ellen Employee starting it? "If it starts on the first pull, we stamp it Honda and ship it." My son's version is: "If Arnold Schwartzenegger can't start it after 5 pulls we stamp it Yazoo and ship it. (We had a Yazoo that he could never get to start at age 10!)

Re gravity, how many of you are old enough to remember David Scott dropping a feather and hammer on the moon?

dtdtdtdt wrote:To be precise, I said dies. I didn't imply or say that they were moulding them from liquid lead like a shooter would do at home.

...)

Yes I know - I was replying to the post above mine ie ShootingSight. I should learn to quote a bit more. Edited now.

High Left wrote:Re gravity, how many of you are old enough to remember David Scott dropping a feather and hammer on the moon?

If you don't remember the moon, there's always the world's largest vacuum chamber.
https://www.youtube.com/watch?v=E43-CfukEgs

I doubt very much, after so many decades using lead slugs, that the makers give s**t about the weight of their lead slugs. Me thinks they just load a tin/box with a selected number, from 200 to 500 and weigh them and divided by the number of lead slugs within the container?????

Some years ago I switched over to using 'TIN/STANNIC' type ammo and I purchased a small of type scale I bought of ebay. They say that the .22 weighs 14.5 grain and the scale showed that they were very, very close to being correct with each and every 'DYNAMIC' Tin ammo as I recorded them, one by one.

Back when they came on line they got rubbished, with some weird statements, about how the 'DYNAMIC' Tin slugs would hit sideways on? Now me I've been using them both for Target Shooting and Wabbit Hunting and I've NEVER seen and evidence of side on impact's, ALL have shown neat round entry wounds or holes in Targets.

I recall, back when I was on another web site, there was a 'VIDEO' that showed a lead Slug Manufacturer weighing lead slugs. IF I recall correctly and at 72 years young, my memories better than it used to be, they weighed them out 10 slugs at a time from each batch of that production series and then divided by 10 and THAT was the weight they put on the tin/box, but rounded up/down to 2 numbers, one either side of the (.).

I used to have a pellet catcher, behind my back yard range and the mangled lead slugs would go into a melting pot and re-used as .44 & .45 lead balls/bullets for use in my Black Powder guns. Now all it catches are the used 'DYNAMIC' Tin slugs which don't melt!



John D-B.

PS. Hope I ain't bored you too much?

Re: re: gravity.

We did the same experiment with a feather and a ball bearing in a glass tube that had been evacuated. I didn't see the moon drop experiment but certainly remember my physics classes.

John D-B wrote:
Some years ago I switched over to using 'TIN/STANNIC' type ammo and I purchased a small of type scale I bought of ebay. They say that the .22 weighs 14.5 grain and the scale showed that they were very, very close to being correct with each and every 'DYNAMIC' Tin ammo as I recorded them, one by one.

Back when they came on line they got rubbished, with some weird statements, about how the 'DYNAMIC' Tin slugs would hit sideways on? Now me I've been using them both for Target Shooting and Wabbit Hunting and I've NEVER seen and evidence of side on impact's, ALL have shown neat round entry wounds or holes in Targets.

I recall, back when I was on another web site, there was a 'VIDEO' that showed a lead Slug Manufacturer weighing lead slugs. IF I recall correctly and at 72 years young, my memories better than it used to be, they weighed them out 10 slugs at a time from each batch of that production series and then divided by 10 and THAT was the weight they put on the tin/box, but rounded up/down to 2 numbers, one either side of the (.).

I used to have a pellet catcher, behind my back yard range and the mangled lead slugs would go into a melting pot and re-used as .44 & .45 lead balls/bullets for use in my Black Powder guns. Now all it catches are the used 'DYNAMIC' Tin slugs which don't melt!



John D-B.

PS. Hope I ain't bored you too much?

Sounds like you got a good scale. It gets matching numbers to your pellets. The GEM scale that I mentioned is that good while the other one isn't.Quality counts in measurement tools as well as bullets/pellets.

The only time I have had sideways holes were at too high velocity with lots of wobble. .22 bullets out of a 220Swift comes to mind - estimated 4500f/s. A few oval holes with poorly stabilized high velocity bullets.

Never with a pellet. I tested 70 different non-lead (tin), composite (tin-plastic, copper-plastic) and "lead" pellets for accuracy and velocity a couple years ago. Over 100 different tests with 2 rifles. No sideways holes that I could detect but some bounce back out of my pellet trap of plastic bits! I did find the accuracy of the non-lead composite pellets inferior to the lead based pellets. Some did well at 17yds (50') but poorly at 50yds. I took the 3 best non-lead pellets to an outdoor range along with my favorite pellet for that air rifle (RWS54) The lead pellets gave 1" groups at 50yds while the three non-lead ones tended toward 6" at the same range.

John D-B: "I doubt very much, after so many decades using lead slugs, that the makers give s**t about the weight of their lead slugs. Me thinks they just load a tin/box with a selected number, from 200 to 500 and weigh them and divided by the number of lead slugs within the container?????"

I have a friend who owns a cast bullet manufacturing company. He makes 20,000 bullets a day in about 10 different weights and calibers. He is also a Distinguished Pistol Shooter of long-standing. I have bought and shot thousands of his bullets with good success. The weight variation in 38, 9mm, and 45 is in the 0.2gr range out of 115 up to 230gr range. He is much more concerned with the lubrication and swaging for diameter correction than the weight. And yes, he puts 500 in a box, checks the weight, averages, and compares to his standard numbers. If off, they go back in the pot. He has been in business for at least 20 years successfully. He definitely gives a hoot about the quality of his products. He buys lead in 20 ton batches, has them chemically analyzed for composition and measures hardness before accepting a shipment. He has turned back multiple batches much to the anger of the lead producer!!

I've a Fire Arms Certificate and have a Rapid MKII at 40ft lbs and a BSA Super10 with a 22 inch barrel that's at 32ft Lbs, both are .22 and I've TRIED the heavier weighted lead ammo in both rifles and even the Bisley 19 grain ones were dropping to much at 40 yards, compared to the 14.5 grain Dynamic Tin ammo. The latter grouped very tight at 40 yards, all 12/10 shots well inside the 1 inch centre of the targets. I should add here that I often have a wee bit of an altercation with some Air Gunners, with regards to keeping their barrels 'CLEAN!', they say that leading up their guns barrels aids accuracy?.

Lead does foul up the barrels IF one fails to keep up a proper cleaning regime, whereas the Dynamic Tin ammo keeps the barrel as clean as a whistle and IS a better aid to accuracy, that is after the shooter keeps up practicing, which many shooters claim is un-necessary?

I personally make my own .44 and .45 lead balls and bullets and load all of my fire arm bullets, mainly .22.250 that a do mainly when its hissing down of rain or it's snowing. I always weigh the lead balls and bullets and if they are 'LIGHT!' the go back in the melting pot. I did try buying them from gun shops, which are OK for the .22-250 bullets and shells etc but far more costly per single item than melting and moulding them ones self.

I did and still have a .22 Air Rifle skirted pellet mould, sadly I get really ticked off cos 60% of them get re-melted due to not forming correctly and brother do I hate the cost matches.