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Pieter.45
01-27-2009, 07:19 AM
Hello all,

I was wondering:if it makes sense to weigh cartridges and measure their rim,is it important to measure the concentricity of the bullet in the case?Or is it rare they run out(quality ammo like eley match)?
I'v just weighed a batch of eley match and there was a little difference,but no extremes.Most were between 50.9 and 51.1 grains (50%) and some were between 51.2 and 51.5 grains (35%).The others were below or above that and these will be used for training.
As to measuring the rim,I'm still waiting for my tool to arrive,but how much difference is acceptable?
The same goes for the concentricity:how much is allowed?
By weighing the ammo,is it the way to go like this or should I devide them by 0.1 grain instead of 0,3 grain.
All help is appreciated as I'm quite new to the benchrest scene.

Greetings Pieter

DonMatzeder
01-27-2009, 07:30 AM
I have done neither but those that have, have, for the most part, found no correlation between weight and rimthickness to accuracy in quality ammo. When you weigh, the difference could be in the bullet, the powder, or the case. You can not issolate the components. Rimthickness is pretty consistent with quality ammo and runout, according to Calfee is corrected in a match chamber.

Pieter.45
01-27-2009, 08:35 AM
Ah...so all this makes no sense.
It's ok to stick with match ammo which doesn't have these problems.
As to weighing of course you don't know what causes the difference.

tim
01-27-2009, 03:37 PM
Coincetricity is controversial somewhat. I tend to believe in it and have found the better lots of ammo tend to have less runout, I suspect crimp is at play here.

brad541thb
01-27-2009, 06:41 PM
I weighed a whole brick of SK Pistol Match, and I found a range of variation from 51.3 to 52.3. Now some may say that this would make no difference, but I find it strange that the heavier ammo I grouped together seemed to shoot better than the lighter ones. Also I would bet the black or red box Eley will not have that much variation. Probably another reason the Eley ammo is just a little more consitent with fewer fliers. I can't say sorting makes a real difference, but I do know that it is boring to do a whole brick at a time. I gave up on it. I think your better off buying the better ammo if you can afford it.

Rich In Kansas
01-27-2009, 08:31 PM
I did this some 10-15 years ago and found the best ammo of the day, Eley BRG (Cera 1995) made no difference. But with cheaper ammo it did make a difference. But the cheap stuff didn't shoot as good as BRG. Since the lead bullet is by far the heaviest component I would guess it is the component detected as varying. The powder its self doesn't weigh but .7 g (again my memory) and enough variation in it to cause problems probably won't show on most electronic scales. Priming could cause major problems but again I don't think ordinary electronic scales would detect it as if the lead varied .1 you wouldn't detect it.

Pieter.45
01-28-2009, 08:17 AM
So it only makes sense in the cheaper ammo then.
I used to shoot sk standard plus and it grouped really well but in one box I had about 5 flyers.
Now I shoot eley match and it's rare I have flyers.In practice so be it but in a match you don't want that.So I was thinking to check for rim and concentricity on my match ammo.

Joe Haller
01-29-2009, 12:30 AM
About 5 or 6 years ago on this rimfire forum, there was a discussion on weighing, and guesses were made on which component have the greatest variance. I'm retired and have lots of time on my hands. So I weighed three bricks of Wolf Match Extra.

I filed my notes away on that little test - Somewhere . . . A couple of days ago while reading this thread I remembered those notes. Now where in the hell did I put those notes? Found them tonight.

Anyway: I weighing 1500 Wolf Match Extra cartridges. I had an extreme spread that went from 39.4 to 40.6 grains: 1.2 grams. That is not as good as the test run by Brad on a brick of SK Pistol Match. He got an average of .9 in his test.

I set aside the 10 lightest and 10 heaviest rounds. Those other 1480 rounds had an extreme spread of 1.0 grains. Not bad: I have weighed a few boxes of Eley Black Box with a spread of .80 grains.

So: What I did next was to pull the bullets from 5 of the lightest rounds and 5 from the heaviest. I weighted each bullet.

The average weight of the light bullets was 39.71 grains
The average weight of the heavy bullets was 40.54 grains.
That is a variation of .83 grains.

Then I cleaned off the lub with carburetor cleaner and weighed them again.
The average weight of the lub (as close as I could measure it) was .06 gram.
I have two scales that are claimed to have an accuracy of + or - .1 grain. The scale uses in this test claimed to have + or - .05 grain accuracy.

I weighted the powder and then the cases with the primers still active. The brass and the powder variations were so small, I could not measure them with that scale.

My questions at that time were: Will a bullet that weighs .83 grams lighter than another have a higher velocity? Will the weight difference cause a different barrel vibration pattern? Will the bullets exit the muzzle at different point in the muzzle movement?

I think the answer to the first question is no. I checked the JBM ballistics calculator on-line and the two bullet weights gave the same velocity.

I leave the 2nd and 3rd questions for some of you to answer for me.

Brad found that the heavier bullets seemed to shoot better than the lighter ones. Makes sense to me: There can be inclusions of other elements in the lead. They would be lighter than the lead. The more inclusions, the lighter the bullet. If the inclusions are "off-center": Could that weight difference cause the spinning bullet to be unbalanced?

Joe Haller (Mr. Frosty)

brad541thb
01-29-2009, 04:02 AM
Actually Joe after looking at one of the groups I just found out that the heavier rounds from this sorted ammo was 52.3grs. So that is a variation of 1grs.

My buddy tells me if you weigh ammo the ones that weigh the heaviest will be due to the fact that it only makes sense to him that the bullets from these heavier rounds will have less porosity or air bubbles inside the bullet. Makes sense to me. He said that the lighter ones probably will be more sporadic and have a tendency to produce your fliers. Now he said that to me after I told him my results. He said it makes sense to him, and I guess was thinking out loud or telling me his theory on this. I do know Don is one smart cookie. Now I am not saying that this is proof that this is the way it is. But you do have to wonder from my results that Don may just be right.

That same SK Pistol Match ammo that I weighed, I played around with tuner weights shooting the 21oz total tuner weight(that's the regular 8oz Hoehn tuner with a 8oz weight screwed in next followed by a 5oz weight on top of it), and this ammo was shooting holes. I shot this one and some more that were below .150ctc I believe. I then shot a 242 USBR I believe with the same ammo. Not too shabby at my range. This group was shot with a box that weighed 52.3-51.8grs.

http://www.hunt101.com/data/546/IMGP1994_Custom_.JPG

Here's a few more I shot from that same ammo I sorted that were the heavier ones.

http://www.hunt101.com/data/500/medium/23790IMGP0029.JPG

I honestly don't think this was a coincidence. I also shot 2 more back to back 10 shot groups that were under .300ctc which is pretty good for 10 shot groups.

I subtracted .204 for bullet diameter on all these groups. So if you want to subtract .224, take .020 more off of each.

I can honestly say that the lighter ones out of this same brick didn't shoot as consistent as the heavier ones.

Pieter.45
01-29-2009, 06:36 AM
This theory has 2 camps:believers and non believers.
I recon myself to the first.
How can you have utmost accuracy with different bullit weights,even minimal.
Concerning the eley match I've weighed 4 bricks now and I had no more than .8 grs difference neither.
And with cheaper ammo I've had more diffference too.
So like I presumed,top notch ammo has less difference.But there still is difference.
I don't know but I presume this goes for the rim thickness too?I am about to receive my gauge(normally next week) so I will find out soon.
I was seriously thinking of measuring and weighing the ammo I will be using in a match.

alan k
02-13-2009, 02:00 PM
20 to 30 years ago rim thickness was a much bigger issue. In those days we used Win and Rem. "target" ammo for practce and the thickness spread could be great. Even Eley had to be checked. Todays Eley the spread is small, BUT in every box I have checked there seems to be one or two "skinney" ones. Sooo in order to go to a big match with your head screwed on straight it pays to throw out all ammo out of range. That way all fliers belong to you, or maybe it was your scope.

One of these days I'll run the oddballs both rim thickness and weight through my CHRONY.

Rich In Kansas
02-13-2009, 03:15 PM
Seems I always remember the bad shots. Two years ago at a tournament at Mill Creek I had a dud on the 23rd shot of the 6th and last target. It had a noticeable milder sound and hit low for a zero. Would weighing have detected it? I don't know. From the sound I would guess it was short on powder. If no powder at all, the primer I don't think would have got it to the target 50 yards away. Might have even stuck in the barrel. Maybe xray would help.

Last night at a indoor 3p match I had a round that would not chamber in my Martini. I sat it aside in the loading tray and checked it later. The bullet was not fully seated in the case and was cocked. I think I paid about .18 cents for that round.:rolleyes: I wonder if I can sell it on ebay. Rich

lead head
02-13-2009, 04:35 PM
Back around 1982/1984 when I was on a real budget trying to raise children and have a little money to shoot too I weighed my ammo that I shot in 22 silhouettes. I was shooting Winchester super-X and having good luck with that system. These were copper wash bullets and they wieghted about the same.The nominal weight was 51.8 grs and back then they seemed to shoot lites out. I have some left now and they won't shoot for a hill of beans. Back then we shot open sights (I could see back then) and in my teeny little mind they seem to shoot great.
We didn't check the rim thickness back then or at least I didn't read about it anywhere. Now the older I get the less time I seem to have so I just buy better ammo and spend that time shooting.
MHO
Larry

_Shorty
02-14-2009, 01:47 AM
Just for a minute, ignore your stance on sorting, by any means, weight, rims, whatever. Ignore the fact that you think it might/does work, or, ignore the fact that you think it doesn't/can't work. Just for one minute, you have no stance on sorting, good or bad. And for that minute, consider the following.

Let's say I have two rounds:

Round 1: 51.7 grains
Round 2: 50.8 grains

What are the chances that both cases weigh the same? What are the chances the primer in both weigh the same? What are the chances both powder charges weigh the same? What are the chances both bullets weigh the same? I think the most important question is, what are the chances that those two complete rounds are the same? Can you honestly answer anything other than absolutely zero chance?

Now, let's say I have two more rounds:

Round 3: 51.3 grains
Round 4: 51.3 grains

What are the chances that both cases/primer/powder charges/bullets weigh the same? What are the chances that those two complete rounds are the same? Not 100%, but definitely not zero, right?

Any chance better than zero is most definitely better than a guaranteed exactly-zero chance, wouldn't you agree? You have no way of knowing where the difference lies between a round that weighs 51.7 grains and one that weighs 50.8 grains, there's absolutely no debate there. 51.7 grains is different than 50.8 grains, period. There are several components that could be different. Any one, or all, of them could differ in each round. No matter which component or components are responsible for the difference, the difference is there. The chances of two rounds that both weigh 51.3 grains being similar and performing similarly has certainly got to be higher than two rounds with vastly different weights performing similarly.

Manufacturing tolerances of individual components, and assembly tolerences of all components being added together, obviously vary, and vary enough to combine into rounds that are measurably different. If they weigh different amounts, you are guaranteed that they are different, no matter where the difference lies. They have different weights, so they absolutely do differ in one or more ways. If they weigh the same, you're not guaranteed that they're the same and will perform the same. But the chances of them being/performing the same are much better than ones that are guaranteed to be different.

Guy Pike
02-14-2009, 05:35 AM
Really, if you think sorting will help you in some way, it will! Mental attitude is huge. I get better times out of high school x-country skiers by using "secret" waxes and voo-doo stuff. Some might work for a hundred yards, some are pure head games. When interviewed at the end of a race they all rave about coaches "special" wax,etc.. Demoralizes the opponents and makes me a guru of sorts. Bottom line: They think they're fast, they're fast. Buy the highest quality ammo, sort it to what ever level you think is best, go into the match with no ammo worries. How can that be anything but good? Also kills time when it is below zero in the Great North! Good shooting, Guy

_Shorty
02-14-2009, 05:42 AM
Excellent point! At the same time, I don't think mental attitude has much to do with 50.8 vs. 51.7 & 51.3 vs. 51.3, do you? Even if you don't think it will make any noticable difference in where they hit the target, is it really that much of a stretch to think that two rounds that are 51.3 grains and 51.3 grains are probably much more alike than two rounds that are 50.8 grains and 51.7 grains? I'd sincerely like an honest answer to that simple question.

Pieter.45
02-15-2009, 04:35 AM
I don't get it.
I've checked a batch Eley match.There were a lot of differences in concentricity.About half had more than 3/100 mm runout.You can actually see the worst bullets wobble in the concentricity gauge.
So I checked the Lapua Center-X out which I still had.These were much more consistent:almost no runout,only 0.3grs difference in weight and a more uniform rim...
So sorting has impact?Yes and no.On the Eley you get a bit better groups on sorting the ammo.With the Lapua I noticed no gains.
It all depends on the quality you start with.I find it strange Eley is "inferior" in consistency compared to Lapua.But sorted Eley outshoots Lapua in my case.

Guy Pike
02-15-2009, 11:31 AM
So by buying high quality ammo and sorting it you found some that shoots well and are at ease with the performance potential of your ammo?

Pieter.45
02-16-2009, 06:41 AM
Well yes.But you gain little with a lot of work.It's all in the game I guess.

Bill Wynne
02-16-2009, 04:33 PM
One of the reasons that I am into rimfire is that I do not have to mess with weighing and loading ammo.

I buy the better stuff and my life is simpler.

If you want to reason out where the variation in weigh is consider this:
If the loaded round weights 50 grains and the bullet weighs 40 grains the bullet is 80% of the weight so it is likely that it will have the most variation.

If the amount of powder is 1 grain in most of the cases and one has 1.1 grains of powder then it an increase of 10% and almost no weight at all.

This stuff will drive you crazy if you let it. You may become a basket case.

Concho Bill

Will Durant
02-16-2009, 06:44 PM
I cast my vote with Shorty.Will

Guy Pike
02-16-2009, 10:02 PM
Two rounds that are identical in weight are indeed identical..... in weight. The bullet being the largest contributor to the total weight of the cartridge might allow one to draw many conclusions ie the rounds are identical and should shoot to the same point of impact or possibly one has a big void in the bullet and the other has no powder. They weigh the same but are not going to shoot alike. Pietr mentions a lot of work for a small gain. The law of diminishing returns applies here. In a contest that is won by thousandths of an inch the little things count. And then some one proves me wrong sometimes. I have neither the equipment or skill to compete at a competitive level outside my own little circle but I do buy the ammo that my guns perform well with. I have Eley, RWS , Lapua, Fiocchi, and PMC Target 22 on hand. I don't sort any of it because I'm comfortable with it's performance.[/I]

_Shorty
02-16-2009, 10:24 PM
Who said anything about two rounds being identical simply because their weights are identical? I'll try this another way. Ignore your thoughts on sorting. You think sorting does work? Fine. You think sorting doesn't work? Fine. You think sorting can work? Fine. You think sorting can't work? Fine. All completely besides the point. Ignore the answer to any of those questions. Ignore the act of sorting and anything it could or could not accomplish. You've never heard of sorting in your life and have no idea what it might be. OK? This is just a simple exercise, and you can resume believing your previous beliefs immediately after taking part in this exercise. But right now, during the exercise, you have no beliefs on the subject because you've never heard of it. Now, on to the exercise. There are only two questions. Answer each one with only a yes or no, nothing more.

1) In the first case we have a 50.8-grain round and a 51.7-grain round. Do you think the chances are very high of these rounds being similar?

2) In the second case we have a 51.3-grain round and another 51.3-grain round. Do you think the chances of these two rounds being similar are higher than the rounds in the first case?

Douglas
02-17-2009, 05:45 AM
My little foray into this venture: I bought a scale, got all set up, ten little trays, brick of Wolf ME, sorted by 0.1grs. took forever to do, very very boring, I thought to myself, what the heck are you doing. Got all done with the brick, I thought, I'm gonna check my work and guess what? Weighed one tray and got new values, what a waste. Then I lumped them into three piles 0.3grs, figured the largest pile would shoot the best, it didn't, what a waste o time. Thanks, Douglas

Guy Pike
02-17-2009, 02:25 PM
1. yes 2. yes

brancher
02-18-2009, 09:40 PM
We had this discussion a few years back, weighed and variances were about 1 grain. And what we discovered was the shorter barreled rifles (under 20") shot better groups with the ammo that was closer in weigh i.e. heavy with heavy and light with light. But when shot in a long barrel like Anschutz 690mm (26.7") or a Remington 40X (I think 28") it was not such a difference (but then again much better rifles). As I remember it someone later did the same experiment but considering velocity and choreographed it and the velocity range were larger on a short barrel vs. long. However they were closer on short barrels when weight was similar. Thus I have started buying longer barreled rimfires so I don't have to worry about sorting my bullets. yep lazy.

Pieter.45
02-22-2009, 01:55 AM
I did some experimenting.Weiging has some influence,as does rim thickness.But the most influence has bullet runout.I sorted the really bad ones(up to 1/10mm and yes it's Eley match)and they shot groups about 5mm bigger as usual.
As posted in the other topic inserting the round fully by hand helps too.

RandyG
02-23-2009, 10:25 AM
Weight sorted some Lapua Master-M (X-Lot) this last weekend and here is what I found:

1000 rounds sorted

≈ 20 rounds between 51.65-51.85 grains
≈ 400 rounds 51.6 grains +/- 0.05 grains
≈ 560 rounds 51.5 grains +/- 0.05 grains
≈ 20 rounds between 51.25-51.45 grains

I was able to sort an additional box [of 50] from the lot and easily end up with 1000 rounds between 51.45-51.65 grains.

This was A LOT of work to sort out less than a box worth of outliers and I doubt it will have an impact on my groups (we'll see once it warms up enough to get out to the range) but what else is a snowbound bloak from up North supposed to do with his free time.

RG

3/1/09 - Sorted another 1000 from the lot. Here's the new totals.

≈ 60 rounds between 51.65-51.85 grains
≈ 930 rounds 51.6 grains +/- 0.05 grains
≈ 980 rounds 51.5 grains +/- 0.05 grains
≈ 30 rounds between 51.25-51.45 grains

Now if it ever gets warm enough to do some shootin, we'll see if it makes any difference.

Bill Wynne
02-23-2009, 10:35 AM
Randy,

Try your two extremes together in four or six shot groups and see if they are worse than the normal.

Concho Bill

RandyG
02-23-2009, 10:44 AM
Randy,

Try your two extremes together in four or six shot groups and see if they are worse than the normal.

Concho Bill

That's exactly what I intend on doing..........once it warms up enough :D.

Cheers
RG

BrentD
02-23-2009, 11:13 AM
Do a statistical analysis if you really want to do this correctly. It has been done by others sorting other flavors of ammo. The answer seems to be it does not matter, but a true statistical analysis would really help put a final answer to this question.

Brent

_Shorty
02-23-2009, 09:55 PM
You'll just ignore the results if they don't agree with your already made up mind anyway. *shrug* (There are statistically significant results out there already that show it can help, just depends on the ammo in question. It doesn't help with all ammo, but how that translated into "It doesn't work at all, with any ammo, ever!! n00b!!!" on this site is beyond me.)

BrentD
02-24-2009, 05:45 AM
Sadly, yet another opportunity to inject some objectivity is rained upon.

Shorty, I don't have a dog in this fight, so I don't have a preconceived opinion.

If you know of "statistically significant" tests, wherefore art they?

Those that I have seen have shown no effect. That's not my preconceived notion. That's the facts. Are you the one shrugging?

Brent

_Shorty
02-24-2009, 07:08 AM
I've seen tests that say it does/can help, and tests that say it doesn't/can't. (Spend some time with google if you want to read about ammo sorting tests. I've no desire to do that searching again.) Even done some testing of my own, and with cheaper ammo (such as Eley Target Rifle) it helped, and with more expensive ammo (such as Eley Match and Tenex) any differences that may be there were so small they got lost in the noise. Like I said, all depends on the ammo you're using to run the tests with. Obviously when weeding out oddballs it is harder to spot the difference when the difference between the majority and the oddballs is smaller, as is usually the case with more expensive ammo. Are you going to notice a .25" difference? Are you going to notice a 0.025" difference?

Whenever the sorting discussion crops up, the people that are against it seem to conveniently forget that part of the reason sorting by things such as rim thickness can be such a waste of time these days is because competitive shooters used to sort by rim thickness in the past. Sorting by rim thickness used to make a big difference. Manufacturers caught wind of the practice, saw a business oppurtunity, and decided to tighten up their manufacturing techniques, giving us closer tolerances in rim thickness straight out of the box today, and charged us more money for the tighter tolerance ammo. The practice itself worked before this change came about. And anyone that debates that is off their rocker. I'm not saying the practice is still relevant today, not in all cases. But the theory behind the practice is solid. The fact that manufacturers took it upon themselves to give us ammo that no longer benefited as much from the practice, by essentially removing the variable for us, doesn't change the fact that the theory is solid. Just means they've done something about the reasons the theory was developed in the first place.

MKnarr
02-24-2009, 07:13 AM
In the past on another forum, I have presented statistically data in a number of experiments that showed there was no difference when sorting by weight to anything close to a 95% confidence level. In one experiment, I presented data using Eley Club, Eley Match, Wolf Match Target and Lapua Super Club. The highest confidence level I got was P = .778 that there was a difference. I was accused of not knowing how to perform statistical tests and in the case of the Eley Match, the unsorted actually had slightly smaller groups than the sorted and Shorty accused me of fudging the data because his pre concieved notion was that that could not happen. Since I spent a career of designing, running and evaluating experiments for the semiconductor industry, I thought I knew how to evaluate experiments but Shorty convinced me that I didn't so the data was removed.

As he pointed out, you either believe or you don't and no amount of hard data will change your mind. But let one guy claim "I got better groups sorting ammo X by ....." and some will jump on the band wagon. I guess on cold winter nights, it is better than drinking yourself into a stupor.

Just My honest opinion because I no longer present facts.

BrentD
02-24-2009, 07:41 AM
I've seen tests that say it does/can help, and tests that say it doesn't/can't.

Which is to say that almost certainly most, if not all of these tests did not do statistical evaluation. And there in lies the problem.


Are you going to notice a .25" difference? Are you going to notice a 0.025" difference?

If that is my objectiven and I design a statistically appropriate test - yes, of course.





Sorting by rim thickness used to make a big difference.

I do not dispute it. But I live in the present, not the past.


MKnarr understands the issue quite well. And I have a good deal of faith in the results he posted. Hence my initial comment.

Now RandyG has sorted some ammo to test this idea on another make and model, and Bill Winn made a good suggestion of how to set up a comparison. All that is needed is some statistical analyses and perhaps there may begin to be enough consensus to lay this puppy to rest at last. Or maybe their results really will be different. I'll be interested to see them.

RandyG
02-24-2009, 07:46 AM
If I get bored enough I might just sort the other 3 bricks as well. This will give me many more data points and increase the sample size of the outliers. As Concho Bill suggested, I will group the low and high outliers together and see how they shoot. I will then compare that with those that have a tighter distribution. The problem here is that the VAST majority of this lot is very tight weight wise. I have done this on some Remington Subsonic HP's I was hoping to hunt with. These had an extreme spread of over 5.0 grains. Even though I did not do a statistical analysis on these (sorry Brent) there was no doubt in my mind that the heavier ones that measured the same shot the best.

I understand the "prove it" attitude all to well and do not have a problem with that. I've worked in electronics industry for going on 25 years. I'm currently in the Process Engineering Dept. where I work. I've worked with some very brilliant people over the years. These people (I would call them funny people but that phrase is already taken) have an unbelievable understanding of Physics, Quantum Mechanics, etc.. If they cannot explain something they start going off in directions that you will never be able to get me to buy into (a fourth dimension?). I actually enjoy working with them. They'll come up to me and ask for my help in running a test for them or something. I'll say to them "that will never work" and they get a real perplexed, almost annoyed look on their face. They scoff and tell me to run it anyway. Then when it fails, they ask why it failed. I'll say I don't know and then they walk off muttering something about my mama. Sometimes there is an art to doing something and it cannot be explained. Sh@t happens, and if you can't explain it, oh well move on.

If I had to guess (and I really shouldn't put this out here) I would say the individual who mentioned the possibility of voids in the bullet might be onto something. If the void was in the center of the bullet, there would be little/no change in the impact location. This could explain why some of the most extreme outliers do not drop out. Others could have the void considerably off center and result in a flier. This might also be happening throughout the samples that measure good also. I could imagine that a larger bullet with just the right size void could measure good but still fall out if the void was off center.

Oh well, life goes on. I'll let you know what happens with my test once it gets a little warmer up here. I'll try and be as scientific as I can. If however nothing explainable comes out of it, I'll crack a beer when I get home and get on with my life.

Cheers,
RandyG

_Shorty
02-24-2009, 07:58 AM
MKnarr, you believe your data, but not someone else's data because it disagrees with yours. Even if their data makes a stronger case. Nobody can possibly run a good test besides you, because everyone else is inept. You believe your data is more sound, and so anyone that has data showing something else has to be a fool. Unless I'm mistaken and it was someone else, you even thought the statistics professor who was in on the discussion didn't know anything about statistics. You remind me of Archie Bunker.

tim
02-24-2009, 04:35 PM
In the past on another forum, I have presented statistically data in a number of experiments that showed there was no difference when sorting by weight to anything close to a 95% confidence level. In one experiment, I presented data using Eley Club, Eley Match, Wolf Match Target and Lapua Super Club. The highest confidence level I got was P = .778 that there was a difference. I was accused of not knowing how to perform statistical tests and in the case of the Eley Match, the unsorted actually had slightly smaller groups than the sorted and Shorty accused me of fudging the data because his pre concieved notion was that that could not happen. Since I spent a career of designing, running and evaluating experiments for the semiconductor industry, I thought I knew how to evaluate experiments but Shorty convinced me that I didn't so the data was removed.

As he pointed out, you either believe or you don't and no amount of hard data will change your mind. But let one guy claim "I got better groups sorting ammo X by ....." and some will jump on the band wagon. I guess on cold winter nights, it is better than drinking yourself into a stupor.

Just My honest opinion because I no longer present facts.

Hey, if you're going to take your valuable time and effort to do tests then please post it up here. There's always going to be someone that takes issue or gripes but it's a worthy excercise and lots of guys who never post do, in fact, appreciate it. You're providing a community service, keep it up.

digisol
02-24-2009, 06:18 PM
An interesting topic, but either way you go it's now common to have most shooters who care at least a little about winning will weigh their RF ammo and those who do always shoot better and with the same gear than those who don't bother to weigh their match grade ammo.

It's pretty simple to watch shooters and see what ammo they use and then see their scores after the smoke clears, the stock Eley Match gets the nod, but other cheaper ammo that is weighed does nearly just as good, the problem with the cheaper stuff is the vast difference in weight, and that means an awful lot of plinking rounds are left over.

_Shorty
02-25-2009, 02:03 AM
Or for fouling in after cleaning, before shooting for-score.
and that means an awful lot of plinking rounds are left over.