If you don't want to learn about statistics, that's fine. Just saying, nobody well versed in statistics will tell you that ES is a good predictor of anything. It literally predicts nothing. I'll leave it there. Up to you to learn about it or not.
Match Ammo Lot Consistency over the Chronograph?
- Thread starter grauhanen
- Start date
If you don't want to learn about statistics, that's fine. Just saying, nobody well versed in statistics will tell you that ES is a good predictor of anything. It literally predicts nothing. I'll leave it there. Up to you to learn about it or not.
Although this is a bit of a digression or drift from the intent of this thread, this leads to an important question. (I don't mean to put you on the spot but I see this as a good opportunity to have more information.)
Your comment above suggests that you believe that it's not so much ammo that is responsible for performance as differences between the bores from one rifle to the next. Ten good rifles shooting the same lot of match ammo will produce ten different answers or results. While some of them will be very similar, some rifles will shoot the ammo well, some will not.
Another way to view it is that there is no such thing as a bad lot of ammo, it's just necessary to have the barrel that will shoot it. Or to put it another way, every lot will shoot well if the right barrel is found.
The question is the following: is there such a thing as match ammo lots that will shoot well in all good shooting rifles? The follow up question must be is there any match ammo that won't shoot well in any barrel?
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For those readers wondering about the intent of the thread, it's about how consistent are match ammo lots. In other words, within the same lot, how much do mid to high tier match ammo differ from one box to another?
Again, there's no need to flog this. If anyone wishes to ignore ES that's okay. I don't want the discussion to be about whether ES figures have any value.
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
Shorty, thanks for posting your 100rds shot data. most rifle combos just aren't as tight as their owners would like to believe.... when you increase the sample size.
I really appreciate the data table which shows how little the chrono numbers of ES/SD actually relate to your target IF the sample size is increased. The numbers are similar yet the results on target are anything but (lot to lot).
The only way to really know how any lot shoots in your rifle... is to shoot it in your rifle in sample sizes that matter while counting ALL of the shots. Sometimes that 'pulled' shot isn't
Eley Tenex 1022-03228 - wouldn't it be awesome to get this level of accuracy all the time.
Jerry
I really appreciate the data table which shows how little the chrono numbers of ES/SD actually relate to your target IF the sample size is increased. The numbers are similar yet the results on target are anything but (lot to lot).
The only way to really know how any lot shoots in your rifle... is to shoot it in your rifle in sample sizes that matter while counting ALL of the shots. Sometimes that 'pulled' shot isn't
Eley Tenex 1022-03228 - wouldn't it be awesome to get this level of accuracy all the time.
Jerry
I don't know how you got that from what I said. I didn't say CCI Standard and Eley Tenex are the same. What I said was manufacturing isn't perfect. Random variations exist. While CCI Standard is likely to show larger variations and Eley Tenex is likely to show smaller variations, even the Eley Tenex will show variations. It is possible for Eley to produce a lot of Tenex that is garbage in every gun, but not as likely as with CCI Standard. Looking only at the pool of Eley Tenex, it is still possible to have some bad-for-Tenex lots that shoot noticeably worse than the average lot of the stuff. What I'm trying to say is that even if you have a couple lots that are very similar in tolerances it is possible for a given gun to prefer one over the other due to one or more of those small variations present in its characteristics.
I just tested five lots of Eley Tenex in my bench gun. It showed a marked preference for one of those five. That doesn't necessarily mean your gun would show the same preference. Some of the characteristics of that lot got along better with the state of my gun than the other lots. Case length? Case body diameter? Rim thickness? Base to driving band? Who knows? Shooting it told me which one to choose for that gun, though. As I'm sure many of us have, I've done a fair bit of lot testing with friends trying the same lots in similar guns. Sometimes we'd see similar performance among lots, and sometimes we wouldn't. You can certainly have generally more consistent characteristics among a few different lots and have them shoot generally better in more than one gun. You can also have one gun that simply freaks out if one variable is out of its own tolerance range. Maybe it will shoot most lots pretty well, but get one lot that has a case length that's pushing the bullet out into the rifling a different amount and it goes to crap. But that lot shoots about as well as the next lot in another gun because it isn't in the range of importance in that other gun. You never know until you shoot it. One lot showing a more consistent SD for MV doesn't necessarily mean it will shoot better. It might have more consistent velocities, but it might also have a bullet exit time that sucks for your particular barrel/gun.
*happy dance*
Purolator guy was just here.
Now, if only the range weren't shut down for a few days for maintenance. Hehe. I always do lot tests without the tuner to see what makes the barrel itself more happy. Now I'm on to tuner tests once the range opens up.Attachments
Mystic Precision
CGN Ultra frequent flyer
- Location
- Summerland, BC
You just won the lottery... congrats and you are going to be tough to beat now.
Jerry
Jerry
How did I get that? This is what you said in post #19.
It seemed reasonable to think you said that ten different rifles with the same lot can produce ten different answers (results on target) as to whether the ammo shoots well or not.
I took it to mean that you believed it was the rifle that determined the ammo's performance. As a result, it's not so much the ammo but the rifle that determines what the results will be. In other words, as I said above, every lot will shoot well if the right barrel is found.
Please note that no where did I or anyone else in this thread refer to any CCI ammo -- until you did. It's not clear why.
If I've misunderstood what you said/wrote above, I apologize.
To return to an earlier question: is there such a thing as match ammo lots that will shoot well in all good shooting rifles? The follow up question must be is there any match ammo that won't shoot well in any barrel?
With regard to the focus of this thread, the data above is for two boxes from each lot. Were the two boxes similar to each other or are the results shown an average of the two? Do you have data on how similar the figures were for other boxes from the same lots?
Saying you'll see ten different results isn't the same as saying one factor is irrelevant. The rifle matters. The ammo matters. They're a machine working together. And no two are alike. They can be similar, but some amount of difference is always there in some characteristic(s) of rifle or ammo. I don't know how much lot testing you've done, but I've done a fair bit over the years with a few buddies. We've all seen some trends and some surprises during those bouts of testing, and you're probably the same if you've done a bunch of it. Different guns can like different stuff. Sometimes similar, and sometimes not. I doubt I'll ever see something that shoots equally well in all guns. And there have certainly been times when a given lot in our test batches shot pretty bad in all of our guns. We might have 5 or 6 lots of Eley Match to test, and we all have varying results with them all except lot XYZ that stunk up the joint for all of us. It can happen. Maybe somebody bumped something on the machine that day and it turned out a whole batch that had one bad characteristic. Who knows? I've seen a lot have something noticeably wrong with the lube, to where none of us could fire more than 12-15 of them before they would start having trouble even getting the round to go into the chamber or the bolt to close. It might've shot fine if the lube didn't have something wrong with it, but we'll never know because we can't even get one target's worth out of the barrel. Someone spilled too much of one ingredient in that day, maybe. Who knows? Still people operating the machines that make the stuff. And people are people.
He had five different lots available where I would be able to snag a decent amount afterwards, providing nobody else bought it up in the meantime, so those were the five lots he sent me. And I got two boxes of each lot. I have velocities for every single shot available, including a good number of samples between the muzzle and the target. But the numbers I listed here are for the entire 100-shot test. I don't think there's much value in looking at it as two separate boxes when trying to determine overall behaviour, but you could examine every shot if you wanted to. "I got abc with the first box and xyz with the second box." isn't likely to be more useful than "I got this with these two boxes." A single sample of 100 should tell you a better story than two samples of 50 viewed as separate things. They're not really separate things anyway.
Thanks for your reply, Shorty.
I understand a little about testing and comparing lots of match ammo. Every time I shoot I'm testing, regardless of whether it's at 50 or 100. I understand the vagaries and consequences of shooting outdoors, especially the influence of changing conditions, and how these can skew results.
The reason I started this thread was because of some things I saw while testing over the past three years. Results on target with the same lots were often not consistent from one box to the next. Why was that happening? I had to ask was there any significant variation within a lot. Can shooters expect that some boxes from the same lot will shoot with different results?
This was highlighted and reinforced by an experience shared with me by a CGN member friend here. He sent me word in the spring before my shooting season began that a certain lot of Midas + he recently got seemed to be very, very good. I checked my own recently bought lots of M+ and I had two bricks. Based on his enthusiasm for it, I bought two more. When I got the chance to test it some weeks later, I was surprised to find that it had a mix of good and very modest results. Some boxes, or good parts of boxes, were much better or worse. This didn't surprise me as it was similar to previous testing with other lots of M+. A few months later I received a message from my friend asking if I had experienced mixed results with that lot as he had also.
This wasn't an isolated case of one lot. I had excellent results one day early in the summer when I shot another lot of M+ for the first time. I was so sure that this was the lot for me that I immediately contacted the dealer I bought originally bought it from. I would have bought all he had. There was none left by that time. But that was fortunate for me, because I was never able to achieve results with that lot that were quite so good. There were occasional very good results with that lot, but nothing that could be counted on from one box to the next.
If there is variation within at least some lots that has consequences downrange on target, that seems like it's something worth knowing. If at least some lots have performance variation, it might explain why shooters who may believe they've identified a lot their rifle "likes" later wonder what happened to the magic.
Thanks for the explanation. I agree that when a shooter relies on consistency within a lot it doesn't matter a whit whether they think of "I got this with two boxes". In this situation they're not really separate anyway. When two boxes from the same lot perform differently it's an entirely different matter. Hence the original question of this thread.
Well, every single shot performs differently. There's some randomness to every single shot. Hard to say how the ammo shoots if you only fire one shot. A larger sample size will give you a better idea. A larger sample size reduces the error in your estimation of the lot's overall performance. One box shooting better or worse than the next isn't really looking at two separate samples. They're not the isolated islands that you seem to be saying they are. You're still looking at the same lot. Looking at them as if they are isolated islands unto themselves only muddies up the water more. They are in fact part of the same pool, so if you treat them as such you'll get a clearer view. Saying something like "Box one had an SD of 7.17 and box two had an SD of 6.54, so I wonder why box two performed so differently." doesn't make as much sense as it might seem to at first glance. With a sample size of 50 you've got a 90% confidence interval of (0.883, 1.119), but with a sample size of 100 that changes to (0.918, 1.083). Think of those as your error windows. With a sample size of 50 your error window is from 0.883 below to 1.119 above, but going to a sample size of 100 reduces that to 0.918 below to 1.083 above. So you could be off by +/- 12 % when using a sample size of 50, but could be off by +/- 8% when using a sample size of 100. The larger your sample size the more confident you can be that your estimation of its performance is correct.
With a sample size of 50, looking at those two boxes as separate entities:
7.17 +/- 12% gives you a range from 6.33 to 8.02.
6.54 +/- 12% gives you a range from 5.77 to 7.32.
You can't really say they performed differently because each of your calculated values falls within the other's error range anyway. There's overlap. And that overlap excludes the possibility of them being different. "But 7.17 is worse than 6.54, so they must be different." The amount of uncertainty involved indicates both boxes are probably similar, at least as far as you can tell given the chosen sample size. There must be an absence of overlap in order to call them different with any certainty.
With a sample size of 100 the combined SD changes to 6.83, and the confidence interval changes:
6.83 +/- 8% gives you a range from 6.27 to 7.40.
And in this case, an SD of 6.83 with the smaller confidence interval will tell you a better story concerning how consistent that ammo is than you get from looking at the two boxes separately. Looking at them separately involves accepting more error, more uncertainty, which is what that confidence interval tells you. That's how wide your error window is. The more you test, the smaller that interval gets. And the smaller that interval gets, the more confident you can be that your answer from your sample size will apply to the entire pool. And this is why I grouped all 100 shots from each lot together when I was comparing them, both for group size and for muzzle velocities. Spending $260 for a brick of it to test made sense before spending $2600 on a case of the stuff. And that $260 was enough to want to make sure that my test told me as much as it possibly could, so that I could say with as much confidence as possible that the answer I was looking at was as accurate as it could be. It was going to be a considerable purchase, and I wanted to make sure that if I was going to spend that much money that I was spending it as wisely as possible. I'd rather know the actual answer is probably somewhere between 6.27 and 7.40 than somewhere between 5.77 and 8.02.
Taking another look at your RWS numbers, with one rifle you have a sample size of 396 shots. Combining those SDs into one gives an overall SD of 9.544, and a sample size of 396 gives you a pretty nice confidence interval of (0.958833, 1.041577).
9.544 * 0.958833 = 9.1511
9.544 * 1.041577 = 9.9408
So you can be very confident that your entire lot of ammo shot from that gun has an SD in the range of 9.1511 to 9.9408, for the entire lot, with an average velocity of 1099.1515 fps, based on your large 396-shot sample size.
Leuchtkafer
Member
I never delved much into the statistical arena of analysis, more of a results on paper and intuitive kind of guy. Shorty, your explanation there makes sense to me. When a sample is taken, based on the sample data we're only making an inference as to what the remainder of the batch will be. Naturally, the best sample size to take is the entire thing, but then there'd be nothing left to buy! So, we take a sample that gives us some degree of confidence to invest in a particular lot, but as has been said, "You pays your money and takes your chances". Spend enough time in a manufacturing environment and it's not necessarily as romantic as an outsider might imagine. Anything can happen at anytime, failures in equipment can occur gradually over time or suddenly and catastrophically. The business owner might even make the call to sell a substandard product without downgrading it if they think they can get away with it, despite employees raising their concerns with it. As much as we'd like to believe everything works perfectly all the time and we're always getting the best product, is that actually the reality of the situation? Does the nature of manufacturing explain why box-box results can have noticeable differences?
I've had many end end rimfires. From a manufacturing stand point I've come to the acceptance that pretty well all rimfire ammo is over priced and still garbage compared to what I can make fairly cheap with center-fire reloads. Might be time for some 'cutting edge' .22 reloads.
Thanks, again, Shorty.
Myke, if that's you, the manufacture of match ammo must be such a complex and complicating endeavour that it's a wonder that any really good, consistent lots of ammo are produced. With the results I see with five lots of Midas it doesn't surprise me boxes from the same lot can be much less similar to each other than we'd like.
Myke, if that's you, the manufacture of match ammo must be such a complex and complicating endeavour that it's a wonder that any really good, consistent lots of ammo are produced. With the results I see with five lots of Midas it doesn't surprise me boxes from the same lot can be much less similar to each other than we'd like.
Surely. There are enough variables, enough components, that it makes it virtually impossible to turn out a perfect round. And so, each round is going to vary from the last and the next in some way(s) or another. Maybe you can perfect a way to create cases that are literally identical in every dimension you can measure, every single time. You're still at the mercy of the alloy you're making it with. A little bit of a different mixture ends up at just the right/wrong spot in the rim where the firing pin is going to hit it and the result is a different amount of force trying to crush the priming compound, and so it goes off slightly different than the last/next one. I'm sure you get the picture. Every component can differ from one example to the next, and all those little differences add up to the variance we see on paper. I've received enough boxes of Eley and their crappy trays that fall inside the boxes to have seen a lot of bullets that have been compromised because they've been jarred around during shipping. And the different dimples and creases in them are going to make it fly differently than the ones that are still in much better condition because their trays managed to stay where they were supposed to.
Different manufacturers do manage to make rounds with better/worse consistency compared to all their competing manufacturers. Some ammo is bad, some is good, some is in between. Some don't appear to care whether or not they make really good stuff, just as long as they're making something. Others seem to try harder to make some good stuff, and even try to continue improving. In the 22 LR world we are at their mercy. Reloading is technically possible, but I don't think any compenents we have available are going to allow us to make anything rivalling the mass-produced stuff. So all we can do is pull up to the table and see what's on offer and give some of it a try, and hope for the best. There are plenty of ways to try to whittle down the candidates. Some shortcuts require a bit of thinking and/or planning. But even with a really good plan there is still some element of luck of the draw. I've got my fingers crossed for all the red boxes I just bought, and hopefully will see some good scores after some tuner fiddling. I won't be surprised if I see some average or even poor scores, either. Seems to be the nature of the beast. At least this time I am trying to stack the deck in my favour and will hopefully see a lot more good scores than poor. It *should* be more consistent than the Eley Team, Eley Match, Lapua Center-X, and Lapua Midas+ that I have played with so far in that gun. Hopefully it is.
I don't know if you have seen these but here is what I was mentioning. They wouldn't be allowed in any rimfire competitions though...
https://cuttingedgebullets.com/shop/cutting-edge-bullets/22lr
Since this thread has moved far from it's original purpose, for which I accept some responsibility, it's worth noting the question of reloading .22LR ammo is one that's been raised in the past, especially with the introduction of the Cutting Edge bullets and reloading kits. These prompted some enthusiasts to claim that ammo better than what was available was around the corner.
These bullets wouldn't be allowed in sanctioned BR competition south of the border (or in ISSF position shooting, either). Are they also not allowed in rimfire PRS competition?
In any case, there is little evidence available that reloading .22LR ammunition produces anything superior to what's available from match ammo makers. Reloading components are equally or more expensive than many top tier .22LR match ammos. Reloading consistency is also easier said than done.
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Perhaps the thread can return to the purpose at hand.
The question here is how consistent are .22LR match ammo lots over the chronograph? How they perform on target is another issue.
Is upper tier .22LR match ammo, such as Lapua Midas +, more consistent over the chrony from one box to the next than what's been shown (the RWS Special Match and Lapua Center X) to this point?
