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New Center X accuracy

I've had a few bricks of CenterX that produced submoa at 100 yards.
Also had a few that weren't capable of submoa at 50 yards.
Not a surprise. I blame it on the method of statistical sampling
used at the factory during batch grading. X-Act is Lapua's best,
Midas+ is a step down in testing results with CenterX coming in third.
Some batches produce above their grade, some sling strays.
Statistical sampling doesn't mean it's all going to produce exactly the same results.
It's rimfire, welcome to the assembly line lottery.
 
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Some batches produce above their grade, some sling strays.
Statistical sampling doesn't mean it's all going to produce exactly the same results.
It's not just the batches themselves. It's important to note that not all batches or lots will produce similar results in different rifles. One rifle's very good ammo can be inconsistent in another.

Ammo performance varies by lot and can vary by barrel. Not all barrels are the same -- even barrels from the same manufacturer or of the same model or length. Bore characteristics help account for this.
 
I was at the testing center in April. I bought a case of what shot best at 50M and a case of what shot best at 100M.
I haven’t had a good day wind wise to test them out, but it’s looking like it will be at least as good as the best of the 10-12 lots that I’ve bought in the wild the last couple years. I’ve never had Center X that shot worse than MOA at 50 yards.
Shooting 6x5 targets at 50 yards the worst lots produced high 3’s with the best lots producing high 2’s.
 
One rifle's very good ammo can be inconsistent in another.

I've never had that happen G.
The atmospheric conditions, chronograph or visual inspection explains my problematic results.
Cartridges that produced predictable trajectories in one of my rifles, did so as well in the others.
If it had tight muzzle velocities and minimal defects,
the results were good in all of my rifles.
Didn't matter if it was the Shilen, Lilja, Feddersen, factory barrels from CZ or in my old Marlin 60.
I do understand that harmonics and exit timing can tighten things up a touch,
but if you don't have tight mv's and uniformly made cartridges, y'er results will reek,
unless y'er shooting at a distance where cartridge quality doesn't matter.

Any rifle can hit a dime every time, if'n ya' get close enough. :D
 
I don't think Lapua has changed the product, just updated the box art. I have had comparable results with both old and new versions of Center-X. Where we used to be able to test by the box, we're now scrambling to get a brick of anything that resembles match ammo, hoping we found a magic lot.
 
I am fairly new to the rimfire "discipline". My first experience with a precision 22 rifle a couple of years ago actually put a smile on my face - something I can't say happened very often in decades of other firearms "disciplines". In those couple of years, I have fired literally dozens of different lots of CX, Midas+, Exact, Biathlon, Pistol, SK Red, SK Yellow, SK LR etc etc, and they ALL grouped more or less like the tighter groups in the attached photo out of Vudoo's (the 5 "normal" groups are just miscellaneous lots of different SK and older CX), and was very typical of ALL the SK and Lapua offerings that I have tried. The 3 crap groups circled in red are the "new" box of CX. I personally would not classify those as a couple "flyers".

I'm not blaming the funky groups on the design. But my experience until recently with CX was exactly as guys who I trust with decades under their belts like MB and JBell have preached - buy CX and go compete. No need to lot test when you buy better ammo. So... are those crap groups "normal" for certain lots of CX, as some of you guys are saying? If so, that's unfortunate, as it takes away any level of peace that if you spend $120 on a brick, you'll be good to go. 2+ moa with CX out of a Vudoo isn't cool. At least to me and my budget given the current ammo climate.

Part of me is disappointed, but... we are also talking rimfire "fun". It's not exactly a life or death hobby. Just an interesting twist to my newbie experience with 22. YMMV
 

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Context and intended use is important for rimfire ammo selection. If your shooting NRL22 stuff especially at smaller matches you don't need 1/4 moa ammo to be very competitive, you need excellent fundamentals and wind reading skills. If your shooting benchrest then ammo selection is more important.

I completely understand getting the best equipment possible, I always try to. However don't let that quest get in the way of or attempt to compensate for training what really matters: proper shot mechanics, highly refined fundamentals, and wind reading / wind effect understanding. That's the stuff that separates the good from the great!

Just saying don't forget about the forest for looking at some pretty trees.
 
Context and intended use is important for rimfire ammo selection. If your shooting NRL22 stuff especially at smaller matches you don't need 1/4 moa ammo to be very competitive, you need excellent fundamentals and wind reading skills. If your shooting benchrest then ammo selection is more important.

I completely understand getting the best equipment possible, I always try to. However don't let that quest get in the way of or attempt to compensate for training what really matters: proper shot mechanics, highly refined fundamentals, and wind reading / wind effect understanding. That's the stuff that separates the good from the great!

Just saying don't forget about the forest for looking at some pretty trees.
Agreed, Jesse. But it also seems like getting an accurate read on your fundamentals is a little difficult when you grab a box of 2+ moa CX... no?
 
Since getting my RimX with a Green Mountain barrel I’ve shot maybe 6 bricks of Center X through it with there being 4 different lots out of that 6. They’ve shot anywhere from.2-.4” at 50yds. I’ve never lot tested or really seen the need for it with the old Center X. I switched to a new lot a couple months back and all I’ve done has been sight it in , get chrono numbers to plug into my Kestrel and off I’ve went. No clue what type of groups it’ll really shoot at 50-100yds. Only time I’ve shot 3-5 for a group is checking zero at a match. I’ve won two matches with this new lot so far, so it’s good enough for this game. Haven’t even had time to do a DSF yet due to work and weather. But it’s starting to sound like the new stuff might not be the same. Might be due to Lapua just trying to get stuff out since we all went into full panic mode after the election or could be new machines or new dies.
 
Agreed, Jesse. But it also seems like getting an accurate read on your fundamentals is a little difficult when you grab a box of 2+ moa CX... no?
Oh yes, absolutely. My comment wasn't directed specifically at the point of this thread but rather a general statement regarding chasing the ammo accuracy dragon that is rimfire. Mainly because a lot of new shooters read this.
 
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Finally got out to test the new box center x I bought recently. I could not tell any difference between new and old from 50-300 yards. I was scared as hell cuz I just bought 3 bricks at the inflated prices just so I could have some. Glad my vudoo likes the new cx at least this batch.
 
I've never had that happen G.
I believe you. Many lots will shoot well in many good barrels. But there's no guarantee that they will shoot well in all of them. In your case, the absence of evidence to the contrary doesn't prove that a lot that shoots well in one good rifle will shoot well in all good barrels.

If it it were so simple it would reduce the need for lot testing at testing facilities. Over the phone, technicians at Marengo or Mesa could advise shooters thinking about sending their rifles for testing to save time. "You want a good lot? This one shot well in a rifle yesterday. No need to send your rifle. Save time. We'll send you the last two cases."
 
Shot some more of it today. Rifle is 457 that has Bartlein w Eachus. My 2 lots each of SK+ and SK LRM continue to pile on one another. SK Rifle Match ( 2 lots), Eley Match, Eley Club nearly as good. I've spun tuner in a .250 range looking for positive consistency. Not getting it. One thing I've noticed is I get drastic deviation in horizontal plane. Looks just like drive band damage except it is just as likely to go left. Maybe even more so. 70 yards Almost zero wind.
 
When a batch of 22lr tests extremely well, the word gets out.
I've watched it happen several times over at Killoughs.
You can track lot numbers and amount in stock on the Killoughs site.
Some batches linger for months, some disappear overnight.
Had it happen to me when trying out the first shipment of Eley Benchrest Semiauto.
Results on target and chrony numbers were better than recent orders of Tenex.
I posted the data in my 50 at 200 thread, by the end of the day, that batch number was gone.
Odds are the same thing happens at the factory test centers.
When a great lot number shows up, I bet it's on the grapevine in seconds and gone in minutes.

I've tried to test the find the batch y'er rifle likes.
Chronographed mv's and documented targets from multiple setups/barrels.
Sent bricks of 22lr at 50, 100 and 200 yards and kept track of the results.
I've found that no rifle can make crappy ammo produce predictable accuracy.
What did turn up was as long as the muzzle velocities were tight, the components
were of high/uniform quality and properly assembled, it didn't matter which rifle it was
fired from, the trajectories were tight. It was the cartridge quality that made the difference.
If it produced poor results, the chronograph and visual inspection explained why.
When a batch did well, ditto. ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^


I also think it unlikely that the best lot numbers ever make it out to the consumers.
Those factory sponsored shooters/teams end up with the best quality cartridges.
When you can improve sales by having y'er brand name show up in the winners circle
y'er gonna make sure the competitors are using y'er absolute best product. ;)
 
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I've found that no rifle can make crappy ammo produce predictable accuracy.
What did turn up was as long as the muzzle velocities were tight, the components
were of high/uniform quality and properly assembled, it didn't matter which rifle it was
fired from, the trajectories were tight. It was the cartridge quality that made the difference.
If it produced poor results, the chronograph and visual inspection explained why.
When a batch did well, ditto
It's a fact that no rifle can outshoot the ammo it's given. No doubt misunderstandings of this has caused many a shooter some grief as they look for the one that will cause inexpensive ammo to behave like it's something it was never meant to be. Regardless whether the barrel is custom or on a high end rifle, it can't spin straw into gold. At the same time, since bores are all different, some more than others, there's no rule that says they must all cause the same ammos to perform the same way. Those differences go a long way in explaining ammo performance variation from one bore to another.

Good lots of match ammo don't last long for several reasons. One is that, when someone reports a good lot, others will buy it up if possible because or the intel, not because it's proven in their rifles. It's easier to take someone's word than to go through the trouble of testing smaller quantities of it and then buying a quantity if it is indeed good.

A second reason, and perhaps a more important one, is that there is a relatively small number of cases produced per lot of of ostensibly good ammo. Even if all the cases of ammo produced in a lot are shipped to a single retailer, the total is not great. There may only be a handful of cases of any lot made. Eley Tenex, for example, is typically produced in lots consisting of six to eight cases, numbers that were easily verified not so long ago with the now-discontinued Eley Lot Analyser. The number of cases of any lot of Lapua ammo will also be similarly small, which is less than most shooters would guess. It doesn't take long for a small number of cases of a certain lot of ammo to disappear, especially if someone says it shoots well.

As for the best lots going to sponsored shooters, there's an obvious temptation to believe the idea that ammo makers save the good stuff for their guys. According to a well-known sponsored shooters, however, it's not true that they get the pick of the litter. "It is purely whatever lands at the test centers... And sponsored shooters have no preference - we pick from the same lots everyone else does, available at the time you happen to test." See post #23 from a few months ago here http://www.rimfireaccuracy.com/Forums/showthread.php/13506-Lapua/page2

Regarding the cartridge quality argument, a visual inspection of M+ or CX will only rarely identify "defects" or dents, dings, etc. in the rounds themselves despite the fact that not all visually satisfactory lots will shoot equally well. When the ammo is match ammo visual inspection rarely yields the explanation for inconsistent performance. With bulk ammo, it certainly helps explain why it's often worse than expected.
 
This thread explains my love hate of Rimfire perfectly. I still day dream of some cool hand loading setup that allows me to have complete control. LOL
 
This thread explains my love hate of Rimfire perfectly. I still day dream of some cool hand loading setup that allows me to have complete control. LOL
I’m the opposite. I work a lot and don’t have time to reload. I like the fact that everyone has the same opportunity to buy good Ammo. One day when I retire I may change my mind.
 
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G, y'er right about the better grades of 22lr being extremely uniform in appearance.
It shows up on my targets with spread being all vertical. Very few horizontal strays.
But that vertical shows up as mv spread on my chronograph. :(

Any time I shoot for precision, rimfire or centerfire, my chrony is out front.
It lets me know if that vertical was me, or velocity related.

I noticed that rifles do have a velocity preference.
I have to think that those fps ranges fit the harmonics and exit timing.
My 21" Lilia produced it's best results at 100 yards with mv's in the 1060 fps slot.
The 18 inch Shilen does better at 50 yards with 1100 fps ammo.
The 20 inch factory CZ Varmint barrel is more consistent with the 1070 to 1080 fps cartridges.

All of those numbers mean nothing when the barrel block rig is used.
With the barrel locked in place, harmonics have minimal effect, it's all on ammo quality.
Or, let's be realistic, my ability to time the squeeze to fit wind conditions. :(
 
Tagging Mike @RAVAGE88 in on this. Since he designed the Ravage chamber used in the Vudoos around the Center-X profile, and if all of a sudden "new" Center-X is inconsistent - regardless of lot - in anything approaching a significant sample of Vudoo rifles, he's probably going to have some useful thoughts (not to mention influence...?).

I've run a bunch of different CX lots out of mine, and all were comparable to performance of 24 lots of CX and Midas+ tested at Lapua-Mesa. Of course, I bought the best lot of CX, which happily was only a mm or two different from the Midas+ at 100 meters. In my experience, there is No Way any lot of CX in a properly-functioning Vudoo is going to spew 1.5" groups at 50 yards unless something is wrong with that ammo or something has changed in the components or manufacturing process used in the cartridge.
 
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I shot a NRL22 match today and gave out a couple of boxes to others to test. One of them had a chance to shoot it before the match and he came back and told me it shot great in his rifle and offered to buy what I had left. I guess for some reason my barrel just doesn't like it. Glad it worked well for him and I'll try a different lot as soon as I can get some.
 
I shot a NRL22 match today and gave out a couple of boxes to others to test. One of them had a chance to shoot it before the match and he came back and told me it shot great in his rifle and offered to buy what I had left. I guess for some reason my barrel just doesn't like it. Glad it worked well for him and I'll try a different lot as soon as I can get some.
Same happen to me, my buddies berg, shoots my 25xxx center x well..my SKRM still shoots better any CX I have.
 
Tagging Mike @RAVAGE88 in on this. Since he designed the Ravage chamber used in the Vudoos around the Center-X profile, and if all of a sudden "new" Center-X is inconsistent - regardless of lot - in anything approaching a significant sample of Vudoo rifles, he's probably going to have some useful thoughts (not to mention influence...?).

I've run a bunch of different CX lots out of mine, and all were comparable to performance of 24 lots of CX and Midas+ tested at Lapua-Mesa. Of course, I bought the best lot of CX, which happily was only a mm or two different from the Midas+ at 100 meters. In my experience, there is No Way any lot of CX in a properly-functioning Vudoo is going to spew 1.5" groups at 50 yards unless something is wrong with that ammo or something has changed in the components or manufacturing process used in the cartridge.
I’ve not shot any of the “new” CX, but have some on the way.

MB
 
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This is new lot tested Center X. It barely bested my best old box style, free range CX, but it did at 100 yards., not at 50 yards. This is 200 this morning.
 

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More food for thought on old vs new. Although both chrono readings are good, the old definitely has the edge. It was 93* today.

Ironically, both test revealed the highest velocities on the first shot. Wondering if I might have a carbon buildup starting.

On a positive note, I screwed on my suppressor today with the new CX and it hammers. I suppose the slight additional weight changed the harmonics favorably.

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I’m not finding the newer center x to be as consistent as the old box version…. Still decent, but more prone to flyers/strays.
 
The new ammo from both Eley and Lapua I've heard are not as good as previous year's offerings. I sent in my Vudoo with a previous lot of Center-X that beat out everything they had except one lot of Midas+.

My friend took his rifle in and had the same results with his previous ammo.

Variance on my rifle at 50m

1644625127247.png


At 100m it stands out more:

1644625169710.png

1644625185593.png
 
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Ammo will drive a guy nuts. I am not able to lot test or send my rifle away to a test center. I just buy a case, tune for it and try to maintain the highest average score that it will do.

I have a brick left from a case of SK Standard Plus that shot a 16.2 mm(edge to edge, 50yds) 40 shot group outdoors in the snow at -2C (Anschutz 64MPR). Meanwhile I'm just hoping something shows up that my Vudoo shoots well.
 
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After waiting for what seems like forever, I finally found some new Lapua to test. Of the 8 lots total I received, there were 3 lots of Center X.

In my Phase 1 testing of the first 4 lots I tried there was just 1 lot of Center X and it produced the groups as well as the Virtual Composite of all 25 shots below.

Of the other 3 lots, 2 were Midas+ and 1 was X-Act. This lot of Center X had the best results for the 8 total Phase 1 tests, but there's a long way to go before I know if it progresses thru all 3 Phases of my testing.

Testing was conducted in my ballistic tunnel day before yesterday and if the weatherman's correct, testing will continue again in a couple of days.

Landy
tdsa 3871.jpg


Center X.jpg
 
I’ve seen a lot of vudoo’s that cx is not the preferred ammo. And a lot that are, but isn’t so much of a difference to justify the cost. Then I’ve seen many just shoot CX when they know it shoots other cheaper ammo better. Funny how some refuse to move on and make a change. I get it. Some just want the most expensive ammo to shoot the best after the price paid.
 
Somewhere, somewhen, I read an article on the method used by Lapua
to test samples of ammunition as each batch was produced.
5 barreled actions in fixtures in the testing tunnels.
If the samples produced great results in all 5 barrels,
it was boxed and sold as X-Act, 4 barrels was sold as Midas +, 3 barrels went out the door as Center X.

Same cartridges using the same components from the same assembly lines.
Only difference between the cartridges was test results and the labeling.

So, I have to wonder, how a rifle would like CenterX more than Midas+ or X-Act?

Same ammunition, only factory testing and labeling variations, but the rifle likes the label better?

Rifles can read? :D

Or maybe the method used in statistical sampling,
only tells the story of the sample actually tested,
but the rest of the batch as boxed and labeled
might in truth be much better or much worse
than the test tunnel samples indicated.
Yeah, I'm going with the old concept that statistics lie.
You never know what y'er gonna get with rimfire.
Welcome to the retail lottery. ;)
 
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Somewhere, somewhen, I read an article on the method used by Lapua
to test samples of ammunition as each batch was produced.
5 barreled actions in fixtures in the testing tunnels.
If the samples produced great results in all 5 barrels,
it was boxed and sold as X-Act, 4 barrels was sold as Midas +, 3 barrels went out the door as Center X.

Same cartridges using the same components from the same assembly lines.
Only difference between the cartridges was test results and the labeling.

So, I have to wonder, how a rifle would like CenterX more than Midas+ or X-Act?

Same ammunition, only factory testing and labeling variations, but the rifle likes the label better?

Rifles can read? :D

Or maybe the method used in statistical sampling,
only tells the story of the sample actually tested,
but the rest of the batch as boxed and labeled
might in truth be much better or much worse
than the test tunnel samples indicated.
Yeah, I'm going with the old concept that statistics lie.
You never know what y'er gonna get with rimfire.
Welcome to the retail lottery. ;)
Good point. It’s similar to Sk Std + and SK rifle match. They come off the same line. No idea how they differentiate what round is which. The only difference I have witnessed between the two is the standard deviation. RM as less SD meaning muzzle velocities are closer amongst rounds. I saw an SD avg of RM at 5.6 where SK + was 12-15 SD.
 
Somewhere, somewhen, I read an article on the method used by Lapua
to test samples of ammunition as each batch was produced.
5 barreled actions in fixtures in the testing tunnels.
If the samples produced great results in all 5 barrels,
it was boxed and sold as X-Act, 4 barrels was sold as Midas +, 3 barrels went out the door as Center X.

Same cartridges using the same components from the same assembly lines.
Only difference between the cartridges was test results and the labeling.

So, I have to wonder, how a rifle would like CenterX more than Midas+ or X-Act?

Same ammunition, only factory testing and labeling variations, but the rifle likes the label better?

Rifles can read? :D

Or maybe the method used in statistical sampling,
only tells the story of the sample actually tested,
but the rest of the batch as boxed and labeled
might in truth be much better or much worse
than the test tunnel samples indicated.
Yeah, I'm going with the old concept that statistics lie.
You never know what y'er gonna get with rimfire.
Welcome to the retail lottery. ;)
Statistics NEVER lie! Not once in the entire history of this area of science have they ever lied.

Even on those rare occasions it might seem like they lie, peer review by fellow scientists quickly reveals a mistake and it's rectified.
It's too bad there isn't any peer review for politicians with a bias! They only use the data to support their position while ignoring the opposing data.

The problem, simply put, is that I've never seen more than a handful of people on any forum who have any knowledge whatsoever of how to properly use statistics.

For the most part sample sizes are too small, measurements of things like group size are shoddy at best, often some bias, and no one has the ability to analyze their results properly.

The end result is that most of you make conclusions stating one ammo is better than another or some test is better than another, but in many or most cases, the two may be nearly equal statistically.
Considering that, is there any wonder why posters squabble so much on every forum over anything they're curious about?

Landy
 
Somewhere, somewhen, I read an article on the method used by Lapua
to test samples of ammunition as each batch was produced.
5 barreled actions in fixtures in the testing tunnels.
If the samples produced great results in all 5 barrels,
it was boxed and sold as X-Act, 4 barrels was sold as Midas +, 3 barrels went out the door as Center X.

Same cartridges using the same components from the same assembly lines.
Only difference between the cartridges was test results and the labeling.

So, I have to wonder, how a rifle would like CenterX more than Midas+ or X-Act?

It would be very good to see an article about how Lapua goes about grading its .22LR ammo. Such a source would be illuminating because the ammo makers are very secretive when it comes to such things.

It is absolutely correct that Lapua Center X, Midas +, and X-Act are all produced on the same assembly line and using the same components. Before the ammo is identified and boxed, no one would be able to tell by looking at it what variety it would be. The three ammo varieties are visually identical.

The only reason a rifle would "like" Center X over Midas + or X-Act would be because a particular lot performed better than others. To be more clear, it's not the name or variety that a rifle "likes" but a particular lot that has characteristics that cause it to shoot well in a particular rifle or rifles.

There's no guarantee that the name on the box -- whether it's Center X, Midas +, or X-Act -- will determine how the ammo performs. I've seen a certain lot of CX peform better than some lots of M+ and X-Act both over the chronograph and on targets down range using two different and good rifles.

It's not clear how much testing any ammo maker does to verify how lots of ammo perform. Since M+ and X-Act doesn't always outperform CX, it's possible that actual testing isn't what is primarily used to determine whether the ammo coming off the Lapua production line becomes Center X, Midas +, or X-Act.

Could it be that where in the production run -- beginning, middle, or end -- determines, at least in part, what is likely to become CX, M+, or X-Act? Is it possible that the better lots of ammo tend to come from a certain segment of a production run?
 
Found the email reply from Lapua sent after reading the article on lot grading.
I use the "contact us" forms available on most manufacturers websites, a lot.
Minimizes the misinformation found on line. :D


Original Message-----
Sent: Friday, February 24, 2017 9:42 AM
To: Kevin Thomas <[email protected]>
Subject: FW: Feedback from Lapua website
------------------------------------------------------
------------------------------------------------------
MESSAGE:
By what procedure does Lapua determine if a lot of 22lr coming off the assembly line is X-act, Midas+ or CenterX. I ask as the question came up in an online discussion and no one could produce an answer. Most seem to think it's done by shooting random samples, from each batch, from a number of barreled actions and checking muzzle velocities for standard deviation and extreme spread. Could you describe the process and the numbers that define the grading? I prefer a correct answer to educated guesses.



Reply:


Kevin Thomas

Feb 24, 2017



You're on the right track, but I'm afraid I can't divulge the exact nature of the testing in terms of standards that you're after. Proprietary, and strictly in-house info there. I will say that every run of ammo, either Lapua or S-K, is accuracy tested in a series of five 10-shot groups, as well as a 50-shot composite. The SD and ES are measured and are required to fall within a strict set of parameters, but ultimately, it's accuracy that makes the final determination. Those that pass this initial testing and show the best promise, are then retested. There are repeats of this same testing in several different test rifles, in essence winnowing down the field. If it passes that testing at a certain level of accuracy, it becomes X-Act, or is downgraded to Midas+ or Center-X, depending on where the measurements fall. Testing of rimfires is problematic, as the ammunition tends to be so rifle specific and, for lack of a better term, temperamental. In doing such testing at one of our Service Centers in either Germany, Finland or Mesa, AZ, I've seen countless examples of Center-X or Midas+ outshooting X-Act, regardless of how they tested during acceptance testing. In those cases, count yourself fortunate that your rifle prefers the less expensive stuff. The bottom line is, you simply can't rate match grade rimfire ammo from best to worst strictly by the showing it makes in the test rifles. It's a start, but you ultimately HAVE to test the lot in your particular rifle to know.

I hope this answers your, at least as far as I can answer it without violating the specifically proprietary methods and specs. If there's anything more we can do to be of service, please don't hesitate to let us know. As always, we'll be glad to help.

Sincerely,

Kevin Thomas
Sales Manager
Nammo Commerical Ammunition

LAPUA Cartridges and Components
SK Cartridges
VIHTAVUORI Reloading Powders
BERGER Projectiles
Nammo Inc – PO Box 2037 – 409 E 2nd St. – Sedalia, MO 65301
Tel: +1 660-826-3232 - Mob: +1-660-596-2274
www.nammo.com | www.lapua.com, www.vihtavuori.com, www.sk-ammunition.com, www.bergerbullets.com
 
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This right here. “Testing of rimfires is problematic, as the ammunition tends to be so rifle specific.” They should start listing what rifles shoot what ammo best. It would give many an ammo type to start with. Again, everyone will need to do their own testing but at least they would have a base to start with. And some may just buy quality match ammo that is cheaper. I for one will never spend the money on Cx or Midas. Way to pricey. My B14 shoots SK ammo well enough. But I’m also not at the top of the game either. I need to work on much more to get better. As I said in an earlier post about my findings between Sk+ and SKRM the main difference was witnessing thru my chrono, the SD for SKRM was 5.6 and SK+ was 12-15.
 
Is it rifle specific?
Or do the results differ due to variations in cartridge quality?
As pointed out repeatedly by more knowledgeable individuals,
small sample sizes produce incorrect conclusions.
Do you base y'er opinion on a single 5 shot group? 10? 25? 40? 50? 100?
A batch can be less than a case or more than 5 cases.
Sample testing to determine quality only indicates the quality of the cartridges tested.
Doesn't guarantee the entire batch will be as good. I think that's the discrepancy
between supposed rifle preferences and brand labels. Is it the name on the label,
or the quality of the cartridges that determine results? I'm going with cartridge quality.
 
“…Testing of rimfires is problematic, as the ammunition tends to be so rifle specific and, for lack of a better term, temperamental…”

I’ve been thinking that for a while now. Sounds like he’s saying that for a given run, the ammo may shoot well in one gun but not the next. Kind of dispels the “common knowledge” that there’s only good ammo and bad ammo. It’s possible to have truly good ammo that performs well in one rifle but not another, consistently. That’s not to say, however, that truly bad ammo can perform well in any rifle on a consistent basis.

Even if it’s a good run of ammo as proven in factory testing, that’s no guarantee it will perform well in your gun. It might
perform sub-par in your gun, or worse than cheaper ammo. That doesn’t mean the testing procedure is bad, or that “statistics lie”, it means ”y’er gun don’t like that run of ammo”. That doesn’t necessarily mean your gun dislikes ALL runs of that make of ammo, it means that particular run doesn’t perform well in YOUR gun.
 
But wait, the 3 labels are X-Act, Midas+ and CenterX....
All made using the same high grade components on the same machines
in the same factory by the same technicians and tested in the same manner
using the same equipment at the same facility, and the results still differ
from sample tested to sample tested. When the folks that make the ammo
have trouble testing for consistent quality and they can test hundreds of rounds per batch,
how is the factory run test facility going to use 40 shots to indicate the best batch for my rifle?
These are all supposed to be almost identical cartridges, but they aren't, are they?
In reality, no two are exactly alike. No two cartridges are identical, no two boxes, no two bricks,
not even any two cases...so how big a sample does it take to determine a preference?

Don't look at me...I sure don't know.
I can't find a brand any of my rifles like.
This week it's R50 getting it done, last week it was SK Biathlon, a month ago Tenex ruled.
Dam fickle minded rifles. :(
 
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So you think, “Sounds like he’s saying that for a given run, the ammo may shoot well in one gun but not the next.” Yes to a degree. But would it really be that bad. So much is the shooter regardless of rifle. And all this ammo coming down the belt is all on the same line under the same quality control. I get some lots may shoot better than others out of a given rifle but it can’t be that much from one lot to the next. I don’t know. Seems far fetched. But again, I haven’t done enough testing with a bunch of brands and lots. I don’t put that much time in to it. I’d make myself crazy. That’s why I just shoot Sk and leave it at that. It’s very consistent and it all groups well.
 
So you think, “Sounds like he’s saying that for a given run, the ammo may shoot well in one gun but not the next.” Yes to a degree. But would it really be that bad. So much is the shooter regardless of rifle. And all this ammo coming down the belt is all on the same line under the same quality control. I get some lots may shoot better than others out of a given rifle but it can’t be that much from one lot to the next. I don’t know. Seems far fetched. But again, I haven’t done enough testing with a bunch of brands and lots. I don’t put that much time in to it. I’d make myself crazy. That’s why I just shoot Sk and leave it at that. It’s very consistent and it all groups well.

The whole magical world of harmonics, I don't understand it but that is my belief that some sort of combination of many factors in ammo and your rifle lead to a match in harmonics. I have ammo that my rifle and my friend's rifle absolutely loves, and then another person's rifle hates it. The ES/SD are consistently good in all the rifles, but the group sizes are very different.

My friend and I had two rifles put together at the same time, mirror specs, so they probably got assembled and reamed using the same equipment, and they actually ended up shooting the ammo pretty similarly. Another friend's Vudoo assembled a few months later shot quite differently same specs, but barrel was made a few months later. Some ammo that had very good es/sd didn't group well in my rifle, but absolutely hammers in my friend's.
 
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The whole magical world of harmonics, I don't understand it but that is my belief that some sort of combination of many factors in ammo and your rifle lead to a match in harmonics. I have ammo that my rifle and my friend's rifle absolutely loves, and then another person's rifle hates it. The ES/SD are consistently good in all the rifles, but the group sizes are very different.

My friend and I had two rifles put together at the same time, mirror specs, so they probably got assembled and reamed using the same equipment, and they actually ended up shooting the ammo pretty similarly. Another friend's Vudoo assembled a few months later shot quite differently same specs, but barrel was made a few months later. Some ammo that had very good es/sd didn't group well in my rifle, but absolutely hammers in my friend's.
As Lapua mentioned in the answered email. Testing of rimfires is problematic, as the ammunition tends to be so rifle specific.” I get it but it’s hard to believe that the QC put in to all this quality match ammo can have so much difference from lot to lot through one gun. Multiple guns, yes, but one gun.
 
As Lapua mentioned in the answered email. Testing of rimfires is problematic, as the ammunition tends to be so rifle specific.” I get it but it’s hard to believe that the QC put in to all this quality match ammo can have so much difference from lot to lot through one gun. Multiple guns, yes, but one gun.

I wonder if it's QC or if it's on purpose. As in, given that everyone can't make the same barrel, chamber, rifle harmonic, if the QC was that all the ammo always loved one gun, then that means there would be a lot of rifles that could never shoot it. So in essence given every rifle/barrel combo seems to have it's own preferred harmonic, having all these different lots of ammo is the only way to go?
 
I wonder if it's QC or if it's on purpose. As in, given that everyone can't make the same barrel, chamber, rifle harmonic, if the QC was that all the ammo always loved one gun, then that means there would be a lot of rifles that could never shoot it. So in essence given every rifle/barrel combo seems to have it's own preferred harmonic, having all these different lots of ammo is the only way to go?
Again I was commenting on lot to lot thru one gun. But say you find a lot that works. Well you’re screwed if u didn’t buy a ton of it. Because the next lot may not be as good. That’s a tough game to play. I can’t think that the differences would be that much. But thru other guns, yes they may not like an ammo another gun loves. I only shoot Sk. And the consistency is pretty good. I don’t get caught up in one lot of the next. I’m in the game to buy ammo as I need it and when it’s available.
 
Again I was commenting on lot to lot thru one gun. But say you find a lot that works. Well you’re screwed if u didn’t buy a ton of it. Because the next lot may not be as good. That’s a tough game to play. I can’t think that the differences would be that much. But thru other guns, yes they may not like an ammo another gun loves. I only shoot Sk. And the consistency is pretty good. I don’t get caught up in one lot of the next. I’m in the game to buy ammo as I need it and when it’s available.
Yeh I just lot test and then buy a case or two and call it good for a few years. Sk red box has shot atrociously out of all my rifles but the yellow box standard plus does okay. About 80% of center-x in terms of group size.
 
Yeh I just lot test and then buy a case or two and call it good for a few years. Sk red box has shot atrociously out of all my rifles but the yellow box standard plus does okay. About 80% of center-x in terms of group size.
That’s crazy that much difference between Sk red and yellow. They both shoot consistently out of my B14. The major difference in the two for me was the SD being better with Red.