Sweet Spot for 22LR Target ammo

[Eoddave27]

Okay, so I have been reading through old post for quite some time now and haven’t really see a post asking the question I have. My sone and I are going to be shooting in our first positional 22 Match next month. We both compete in local PRS matches so the style shooting isn’t new. Using a rimfire past 150 yards however is. My question is in regard to ammo. For everything inside 100 yards both our rifles love CCI SV and consistently shoot sub MOA. Past 150 though I’m sure everyone knows what happens. The velocities are just to inconsistent. Anyway I am looking for an ammo that is kind of a happy medium between precision and price. A sweet spot so to speak. I would love to be able to buy a few cases of Eley Tenex but in case you missed it I have kids . As much as we shoot I just can’t spend that kind of money on rimfire ammo. I also think that with positional shooting a stable shooting position and good fundamentals are more important than using the most expensive ammo I can buy. I just ordered 10 boxes or mid priced Eley, Lapua and SK ammo. I wanted to try some Wolf too but the place didn’t have 50 round boxes. While I know every rifle is different does anyone here have some insight into any specific ammo I should try. I have about 1 1/2 months to test different ammo so hopefully I can find something each of our rifles like and buy a case of one lot number.

 

[brusky]

I've been right where you are and my go to ammo for 50 yards out to 200 yards is hands down SK Pistol Match Special and I've tested almost everything worth shooting past 100 yards. I know ammo will react differently based on the gun but SK PMS hit the sweet spot for me. The best accuracy for the price. I use it in place of Eley Tenex the majority of the time.

 

[straightshooter1]

Eoddave27,

In addition to those you've listed for testing, you might want to try RWW's Rifle Match. From my testing with a match barrel they're almost as consistent as the way more expensive R50 or R100 and they can be had close to what you might pay for Lapua. Also, I've tried SK Pistol Match and SK Rifle Match and they both did well, however . . . in my case, the SK Rifle Match performed significantly better than the Pistol Match and there's not much difference in price between those two.

 

[Eoddave27]

I had the RWS rifle match and took it out of my cart at the last minute. Right now I have Eley edge, Eley Target, SK rifle Match, SK pistol match and Lapua Center x on the way. More than likely I will place another order in a week or so to try out anything suggested here that I haven’t already tried.

 

[45cal4life]

Out to 225 yards, Center-X works good for me

 

[Skok3y]

My Vudoo loved the SK Rifle Match and CenterX. I haven’t tested my other rifles the way I tested it.

 

[FromMyColdDeadHand]

What makes pistol ammo, pistol ammo?

 

[Skok3y]

What makes pistol ammo, pistol ammo?

Usually the powder burn rate, adjusted for barrel lengths. Could be a variety of things depending on manufacturer, but that is usually the most important item.

 

[nhman]

I'm new to the hide and also wondering about this. Im curious what a good ammo for out to 100 would be for practicing the fundamentals, without wondering if it's the ammo or me (probably me). I'm piecing together a 455 with a 20" barrel.

 

[Eoddave27]

I'm new to the hide and also wondering about this. Im curious what a good ammo for out to 100 would be for practicing the fundamentals, without wondering if it's the ammo or me (probably me). I'm piecing together a 455 with a 20" barrel.

For out to 100 yards I have had a hard time finding anything better than CCI standard velocity. You can get a 500 round brick for $25 and every 22 I have shoots it well. Past 150 though it’s velocity is to inconsistent and the 22 matches here shoot from 50-400 yards which is why I’m looking for something that is good for long range but doesn’t break the bank.

 

[Skok3y]

For out to 100 yards I have had a hard time finding anything better than CCI standard velocity. You can get a 500 round brick for $25 and every 22 I have shoots it well. Past 150 though it’s velocity is to inconsistent and the 22 matches here shoot from 50-400 yards which is why I’m looking for something that is good for long range but doesn’t break the bank.

Depends on your target and what you are shooting at. CCI SV can hold MOA for the most part and is cheap. If you are shooting 1/4 targets and want to take out the fliers, you probably want to shoot something else, but based on your comment of practicing fundamentals, you should be fine. I think it is a solid round for cheap. And all my CZs have shot it well.

 

[Alabusa]

Wolf Match Extra worked really well in my rifle. It shot Almost .5 moa.

 

[justin amateur]

Compare for yourself.
Then decide which will do the job.

https://www.rimfirecentral.com/forums/showthread.php?t=1129343

Working on shooting all the brands of rimfire at 200 yards.
50 shots, chronograph results, group size.

 

[nhman]

There is an ammo rating system already in place.
It's the price per round.
6 cents a round or less is bulk.
7 to 10 cents a round is for 25 yard pistol targets.
11 to 15 cents per round is practice ammo for 50 yards.
16 to 20 cents per round is practice ammo for 100 yards.
21 cents to 29 cents per round
is for competition if you don't care if you win.
30 cents per round up is for local benchrest matches.
Lot tested ammunition bought in case lots of 1250 bucks plus per case is true match ammo.

It's true. You don't have to like it, but it's true.

I thought this was interesting .

 

[Eoddave27]

I thought this was interesting .

That is interesting but I don’t think it is accurate in my case. CCI standard velocity that I pay about $.05-06 per round for will consistently shoot 1moa at 100 yards. To me it isn’t worthit to triple the cost of my ammo to shoot a little tighter group at 100 yards for practice. I would rather buy three Times the ammo and practice more. At longer ranges the expensive ammo is the best. There is no question about that. If I was shooting bench rest and wanted to win that is what I would buy. However, I’m not shooting benchrest for tiny groups. I’m shooting positional competitions. In my case a good stable position and good fundamentals have a larger bearing on accuracy than ammo to a point. This isn’t to say I don’t need good accurate ammo. I’m just saying that doubling the cost of my ammo for slightly better performance at 200-300 yards probably isn’t a very good return on my investment.

 

[nhman]

Yeah I agree, bang the for buck is where its at.

 

[justin amateur]

CCI SV, consistent moa at 100 yards?
Damn, I need to find out where you are buying from.
The SV I purchased is showing 50 to 90 fps ES.
That means 1.25 inches to 2.25 inches of vertical at 100 yards.
When shot from benchrest...off hand I'd be lucky to stay on paper.

 

[Hookturnr]

I used to use Norma Match and had some very good results with it. I have since switched barrels and gone to tenex, but the Norma was pretty damn consistent in the stock cz barrel and not priced bad either....in fact, I still have several bricks floating around here.

 

[Eoddave27]

CCI SV, consistent moa at 100 yards?
Damn, I need to find out where you are buying from.
The SV I purchased is showing 50 to 90 fps ES.
That means 1.25 inches to 2.25 inches of vertical at 100 yards.
When shot from benchrest...off hand I'd be lucky to stay on paper.

I bought 2000 rounds from Brownell when they were on sale for $25 a brick. Every brick is the same lot and it has all been sub MOA at 100 yards. I have tried a couple of different lots too and they were all similar. I don’t know what to say if you are getting 2” groups at a 100 yards with it. Everyone who shoots it at the range I use and has a decent rifle gets results similar to mine. Our rifles are nothing really that special either. Mine is a savage MKii FVSR beaded in a Boyd’s tacticool stock and my sons is a stock Ruger precision rimfire. I’m not sure if you have ever seen the battleship targets but my son and I use them as a little contest at the end of the day. Most of the time whoever goes first cleans his side of the target and wins. If it is windy it can be interesting but if it is calm we rarely miss the 3/4” dots at 100 yards.

 

[justin amateur]

1 inch vertical spread at 100 yards is what happens with match quality rimfire.
1/4 inch of vertical spread for 10 fps difference in MV
using subsonic 22lr.
Typical match ammo has an ES less than 40 fps.
If you are getting consistent sub moa at 100 yards
that's some righteously good 22lr.

 

[Eoddave27]

Before I bought my bricks of 22lr ammo I did quite a bit of searching online to see what budget priced ammo people were getting good results with. Almost every sight I went to had the CCI SV performing close to or better than the budget match ammo they tested. It did seem like the really high end rifles didn’t shoot it as well for some reason. In fact one of the articles I read the guy tested with 5 different rifles. If I remember correctly it was a Savage MKii, a CZ455, 2 different 10/22’s and an Anschutz 22. Tha ammo results across the board were similar for all the rifles except the Anschutz. It like the match ammo the more expensive match ammo the best. Anyway almost all of the places I looked had the CCI SV shooting sub MOA at 50 and if it wasn’t MOA at 100yards it was darn close. Now after 100 it starts to show that it is cheap ammo but inside 100 yards it is hard to beat for the money. If I can find the review with the different rifles and ammo again I will post it


Just found it. Interesting results. http://www.dayattherange.com/?p=4691

 

[straightshooter1]

1 inch vertical spread at 100 yards is what happens with match quality rimfire.
1/4 inch of vertical spread for 10 fps difference in MV
using subsonic 22lr.
Typical match ammo has an ES less than 40 fps.
If you are getting consistent sub moa at 100 yards
that's some righteously good 22lr.

Yeah, you're right about match ammo typically being under 40 fps. I feel the better one's will be under 30 and at around 25.

220 shots of CCI SV's through my custom RPRR and recording 10 shot sets, I've averaged an ES of 36 and this was for a few different lots. Likewise in number of shots, for comparison, with Lapua Center X I've recorded an average ES of 26 and for Federal Ultra Match the average ES has been 31 (the Center X's and Ultra Match being of the same respective lot).

Interestingly to me, while the CCI SV's performed better than expected for it's price point, the CCI Green Tag did not.. . . as it only gave me an average ES of 39. So, it's SV's over Green Tag for me for sure.

 

[justin amateur]

I remember reading that article.
1 five shot group to base a conclusion on?
I test 50 to 100 shots across a chronograph to determine ammo quality.
I want to know what is going to happen for an entire box, minimum.
Shooting groups is a start in determining ammo quality,
however one dot one shot targets
are my choice for determining consistency.
If they aren't hitting center, they aren't good enough.

 

[FromMyColdDeadHand]

The next time I go to the range I'm going to do some tests with in two rifles with some WME, Center-X, Midas some Eley ammo I have around and I ordered some SK Rifle Match + (the more expensive of the two rifle versions) and run them in single shot targets and run them past a Labradar. Just waiting for a +45f day with out crazy winds over the break or weekend.

 

[Alabusa]

CCI SV, consistent moa at 100 yards?
Damn, I need to find out where you are buying from.
The SV I purchased is showing 50 to 90 fps ES.
That means 1.25 inches to 2.25 inches of vertical at 100 yards.
When shot from benchrest...off hand I'd be lucky to stay on paper.

This is exactly what I am seeing with CCI sv. I consistently get .5" high or low shots at 50 yards with a 10 shot group. The only consistency is that you will have 1 bad shot every 10.

 

[justin amateur]

What we need is a standardized 50 yard testing target.
A target specifically designed to display rimfire ammo quality.
50 shots in total, all on a single sheet of 8.5x11.
It'd need a grid to allow verification of dimensions.
Record distance, conditions, rifle, ammo brand/type, chrony numbers.
50 aim points, grid underlay, no arguing about results.

Wouldn't be hard to design, but no one would use it.
There's no way to cherry pick when you have to show all 50 shots.

 

[300ATT]

You have to test. Lots of testing at 50, 100, 150 and 200. Ammo that shoots well at 100 does not necessarily shoot well at 200.

Here are the results of the testing that I did:

https://www.snipershide.com/shootin...you-using-for-long-range.6909187/post-7318033

I mostly shoot SK+ as it works decent enough for practice but I noticed more variation in the velocities over Eley and saw random flyers at distance (211 yards). So SK+ for pracise 25 - 211 yards Eley Edge for matches.

 

[Eoddave27]

What we need is a standardized 50 yard testing target.
A target specifically designed to display rimfire ammo quality.
50 shots in total, all on a single sheet of 8.5x11.
It'd need a grid to allow verification of dimensions.
Record distance, conditions, rifle, ammo brand/type, chrony numbers.
50 aim points, grid underlay, no arguing about results.

Wouldn't be hard to design, but no one would use it.
There's no way to cherry pick when you have to show all 50 shots.

You are absolutely right. I very very rarely shoot groups. The only time I really do is during load development or when testing new ammo. I just don’t enjoy it and if it isn’t fun what’s the point right. When I get new ammo I shoot 10 rounds over a chronograph and I’m done. I calculate my drop and test it at different ranges to verify my numbers ar correct. I’m not shooting bench rest competitions as I mentioned to start with. The ammo I’m looking for will be used for positional matches. That is why ammo that can shoot a 10% tighter group at 200 yards but costs twice as much is not a good investment for me. The chances of that 10% making a difference when you are balancing on a baracade shooting at a 3 MOA target at 300 yards is pretty small. That’s why I’m looking for an ammo that is a happy medium between price and performance. I would rather buy twice the amount of ammo and practice. I think that will help me a lot more than that 10% better performance I get out the ammo that cost twice as much.

 

[300ATT]

I tested groups and ammo over the chrono. The SK+ shoots good but recorded a 51 ES (10 shots). Eley Edge had an ES of 22 FPS and and SD of 10. Eley Match was 19 fps ES (again 10 shots) SD of 8. 10 shots of Eley Tenex recorded an ES of 3 fps and an SD of 1 ...

If you don't mind the occational flyer at longer distances for positional .22 shooting then SK+ works well for me.

YMMV

 

[Eoddave27]

Thank you, that is exactly the kind of info I’m looking for. I ordered a few flavors of the SK to try and a few boxes of different mid priced Eley. I ordered a few Lapua too. I’m guessing our rifles will like at least one of these. I’m keeping my fingers crossed for the SK. It is priced fairly reasonable and it seems to be in stock with the places I order.

 

[lash]

What we need is a standardized 50 yard testing target.
A target specifically designed to display rimfire ammo quality.
50 shots in total, all on a single sheet of 8.5x11.
It'd need a grid to allow verification of dimensions.
Record distance, conditions, rifle, ammo brand/type, chrony numbers.
50 aim points, grid underlay, no arguing about results.

Wouldn't be hard to design, but no one would use it.
There's no way to cherry pick when you have to show all 50 shots.

I appreciate your testing and the data that you are developing and providing. However, for those of us that would rather shoot matches and make impacts in positional and movement oriented stages, the bestest of the best is truly not needed. There is much more going on to affect your impact than a minor variation in velocity is going to do.

Each person has things that make them happy while shooting. For me it is cleaning a steel stage at 60 yards or hitting a shaving cream can on a string at 219 yards. At 219 or 325 yards, the velocity spread is much less important to making impacts than a minor breeze moving left to right. Since the next shot may or may not even be taken from the same position or even at the same target, group size or even dot drills are usually not on my mind.

We do often do a 6 dot drill, but it involves getting up off the gun and spinning around between each shot and completion in sixty seconds. See what I mean?

 

[justin amateur]

I gotcha lash.

My comment was meant to be one to make folks grin.
Do you think anyone other than myself would use and post actual crappy results?
Still, it would be nice to be able to have the format.
Not just a single 5 shot group with the claim of all day long.

 

[Eoddave27]

Justin, I for one really appreciate all the time and money you put into testing all the different ammo and posting the results. I actually bookmarked your post on rimfire central and used it to decide which ammo I wanted to try out to start with. Hopefully one of the mid priced options will prove to be good enough for my needs.

 

[lash]

I gotcha lash.

My comment was meant to be one to make folks grin.
Do you think anyone other than myself would use and post actual crappy results?
Still, it would be nice to be able to have the format.
Not just a single 5 shot group with the claim of all day long.

Only if I do my part...

 

[MDrimfirerookie]

this is another one of those really interesting post to me. there are a lot more accomplished shooters here than me, a lot more fundamentally sound shooters than me and a lot more experienced shooters than me. i love to soak up as much knowledge as i can from reading and then going out and practicing when life doesn't get in the way. so thank you everyone who has posted meaningful information.

with that said, the two posts below struck a chord with me.

You are absolutely right. I very very rarely shoot groups. The only time I really do is during load development or when testing new ammo. I just don’t enjoy it and if it isn’t fun what’s the point right. When I get new ammo I shoot 10 rounds over a chronograph and I’m done. I calculate my drop and test it at different ranges to verify my numbers ar correct. I’m not shooting bench rest competitions as I mentioned to start with. The ammo I’m looking for will be used for positional matches. That is why ammo that can shoot a 10% tighter group at 200 yards but costs twice as much is not a good investment for me. The chances of that 10% making a difference when you are balancing on a baracade shooting at a 3 MOA target at 300 yards is pretty small. That’s why I’m looking for an ammo that is a happy medium between price and performance. I would rather buy twice the amount of ammo and practice. I think that will help me a lot more than that 10% better performance I get out the ammo that cost twice as much.

I appreciate your testing and the data that you are developing and providing. However, for those of us that would rather shoot matches and make impacts in positional and movement oriented stages, the bestest of the best is truly not needed. There is much more going on to affect your impact than a minor variation in velocity is going to do.

Each person has things that make them happy while shooting. For me it is cleaning a steel stage at 60 yards or hitting a shaving cream can on a string at 219 yards. At 219 or 325 yards, the velocity spread is much less important to making impacts than a minor breeze moving left to right. Since the next shot may or may not even be taken from the same position or even at the same target, group size or even dot drills are usually not on my mind.

We do often do a 6 dot drill, but it involves getting up off the gun and spinning around between each shot and completion in sixty seconds. See what I mean?

like i said, i'm not the best and i've gone through this with rifle AND ammo. first it was what rifle should i buy. then it was what do i feed said rifle. i damn near went crazy trying to figure it out . its all personal and you need to strike that balance of cost and knowing if it is your or your gear. unfortunately, no one else's experiences are going to be the exact same as yours but hopefully you find some who are close and try what they recommend.

this year has been a blast and i can't wait for 2019.

sorry for the long post.

 

[FromMyColdDeadHand]

What we need is a standardized 50 yard testing target.
A target specifically designed to display rimfire ammo quality.
50 shots in total, all on a single sheet of 8.5x11.
It'd need a grid to allow verification of dimensions.
Record distance, conditions, rifle, ammo brand/type, chrony numbers.
50 aim points, grid underlay, no arguing about results.

Wouldn't be hard to design, but no one would use it.
There's no way to cherry pick when you have to show all 50 shots.

I agree, except at 100, or at least 75 yards. 50 yard performance is the ante to the game. The problem with 100 is that the shooter and the wind can start to have a more pronounced effect. The upside is that it also really highlights the differences in ammo. 200 is the real stuff, but that is like shooting 800 yards with a 308- the noise is stacking up and the groups are still really interesting, but harder to dissect and discern information from the data.

Maybe 50 is a bit too many, but I think you are on the track. It is how many shots in a match just don't go where they are supposed to.

 

[flatland1]

I've been doing a lot of testing various brands & grades of 22RF ammo since building a Stiller 2500XR-based repeater with a Krieger bbl. I had several lots of Eley Match EPS & Tenex. SK Rifle Match & Pistol Match were quite a bit less expensive, and out-shot the Eley by a considerable margin. Also bought 2-box samples of a dozen or more lots of Lapua Center-X; I found one lot # that was good enough to easily justify quantiy purchase, but by the time I'd managed to figure it out, there was no more of that lot # to be found.

Since then, I sold the Stiller, then sent off a couple of CMP 40X & 40XB actions to jelrod for repeater conversions & re-barreled them with Benchmark & Lilja bbls, bought a V-22 action and put a Krieger bbl on it, then last month, bought a couple of V-22 bbl'd actions, one with a 22" Bartlein Kukri, the other with a 18" ACE Ranch. Throughout the past couple of years with all these rifles, I'm still looking at the SK ammo in most cases as plenty good enough for match use out to 100yds. However, when the match director started putting targets from 200 to 300yds out, I moved up to Lapua Polar Biathlon, which costs me double what the SK does. However, even with this stuff, it takes a fair bit of testing to find a lot # that shoots good enough to justify the expense. Biggest problem with all the testing is that it's sometimes not possible to find the time with good conditions to get conclusive testing done before the lots I'm testing are sold out. I've got good supplies of SK Rifle Match & Pistol Match that shoot quite well, and some Center-X & Polar Biathlon that's fairly good....but when I start running short of this stuff, I'm sending the V-22 Kukri out to Mesa to have them identify & locate good lots of both SK & Lapua ammo.

 

[accurate obsession]

I bought 2000 rounds from Brownell when they were on sale for $25 a brick. Every brick is the same lot and it has all been sub MOA at 100 yards. I have tried a couple of different lots too and they were all similar. I don’t know what to say if you are getting 2” groups at a 100 yards with it. Everyone who shoots it at the range I use and has a decent rifle gets results similar to mine. Our rifles are nothing really that special either. Mine is a savage MKii FVSR beaded in a Boyd’s tacticool stock and my sons is a stock Ruger precision rimfire. I’m not sure if you have ever seen the battleship targets but my son and I use them as a little contest at the end of the day. Most of the time whoever goes first cleans his side of the target and wins. If it is windy it can be interesting but if it is calm we rarely miss the 3/4” dots at 100 yards.

View attachment 6983325

Not saying that you aren't getting consistent 1 moa from your CCI SV, I like it too, but if you are you'd better stop loaning and plinking with that ammo and run it in comps only cause odds are the next lot of SV won't do that for you.

 

[Seymour Fish]

Okay, so I have been reading through old post for quite some time now and haven’t really see a post asking the question I have. My sone and I are going to be shooting in our first positional 22 Match next month. We both compete in local PRS matches so the style shooting isn’t new. Using a rimfire past 150 yards however is. My question is in regard to ammo. For everything inside 100 yards both our rifles love CCI SV and consistently shoot sub MOA. Past 150 though I’m sure everyone knows what happens. The velocities are just to inconsistent. Anyway I am looking for an ammo that is kind of a happy medium between precision and price. A sweet spot so to speak. I would love to be able to buy a few cases of Eley Tenex but in case you missed it I have kids . As much as we shoot I just can’t spend that kind of money on rimfire ammo. I also think that with positional shooting a stable shooting position and good fundamentals are more important than using the most expensive ammo I can buy. I just ordered 10 boxes or mid priced Eley, Lapua and SK ammo. I wanted to try some Wolf too but the place didn’t have 50 round boxes. While I know every rifle is different does anyone here have some insight into any specific ammo I should try. I have about 1 1/2 months to test different ammo so hopefully I can find something each of our rifles like and buy a case of one lot number.

A different approach is to find ammo that chronographs Mach 0.92 consistently (that your bbl/chamber likes)

 

[Sieg]

My V-22 Ace Kukri barrel shoots CCI SV surprisingly well, SK Std+, SK Pistol Match, Center-X, and RWS R50 do very well.
Tennex, Federal Ultramatch, SK Rifle Match, Wolf Match Extra are just OK.

At 200 yds the R50 has shot the tightest 25 round group to date. The SV is no slouch at 200 yds either at $0.05 per round.

Haven't tested SK Pistol at 200 yet, though it delivered sub MOA groups at 100, and multiple one ragged hole at 50 groups. I may have hit the Lot lottery with the last brick I bought.

 

[300ATT]

I saw some significant variations between different lots of SK+. If you find one that works buy a case!!

 

[Friar]

Check this out...

http://www.accurateshooter.com/guns-of-week/22lr-rimfire-ammo-comparison-test/

 

[straightshooter1]

Check this out...

http://www.accurateshooter.com/guns-of-week/22lr-rimfire-ammo-comparison-test/

Hmmm??? Gotta me careful about conclusions one might come to when looking as such results. There's so many variables and one can really only run tests from one's own gun to see how any of the ammo might perform. Note the Western Value Pack in the 50 yard test where it came in high on the list. And though it showed high on the list in this test, I'd bet you can't count on it grouping as it did here. It goes to show that one might win the lottery with 25 shots for any ammo . . . but the odds are a long shot in many cases.

 

[Sieg]

I saw some significant variations between different lots of SK+. If you find one that works buy a case!!

My rifle has done well with 3 different lots, though dealing with the lube on Std+ compared to Pistol Match justifies spending a little more.

 

[FromMyColdDeadHand]

Check this out...

http://www.accurateshooter.com/guns-of-week/22lr-rimfire-ammo-comparison-test/

It is interesting to follow the link to and look at the pics of the groups. Gives an idea of the true ability to hit a target.

 

[BillOH]

It is interesting to follow the link to and look at the pics of the groups. Gives an idea of the true ability to hit a target.

I found it interesting that some groups had 4 shots close together with one round completely outside the group. That would probably skew the results. If that one round was closer, what would the final results be??

 

[justin amateur]

Maybe 50 is a bit too many

50 is too many? No, don't think so. Not enough.
Testing ammo y'er looking to determine what will happen for a box of 50.
Testing needs at least that many, in my opinion it needs double that.
I'm not interested in small samples that skew the analysis of quality and consistency.
I want robust numbers that show what will happen during the course of a mornings shooting.
Random acts of accuracy do not impress me. I want full disclosure of what happens.


4 shots close together with one round completely outside the group

That is typical of rimfire. Cartridge defects that cause strays.
Primer amount differences, irregular brass dimensions, asymmetric bullets, irregular seating, lube amounts.
It's why small samples are not useful when testing ammo.
Odd strays lose competitions.

 

[flatland1]

I wonder how old that ammo comparison on Accurate Shooter is? Seems like I saw something just like it about 8-9yrs ago...

 

[Magnetic]

My T1X and CCI SV seem to be getting along ok at 50 yards, and we are still getting to know each other...

 

[justin amateur]

200 yards, SK Pistol Match Special...impressive eh?

CZ 455 Varmint, Lilja EPS chambered barrel, set trigger, Mueller 8-32x44 target reticle, Sinclair bipod

That's a small sample. Nothing I would rely on for a verification of ammo quality.

Total disclosure, 50 shots, provides much more useful information.