Matching Ammo to Rifle Question

[higginsdj]

So I have my own rifle and started to shoot 'reasonable' 50m prone scores (better than 190 out of 200 with whatever ammo I have to hand on an open range). So I hear that it is important to match ammo to barrel but at what level do I need to be to gain anything from this? ie would it get my 190's and turn them into 200's or is it about taking a consistent 10 ring group and making it a 10.5 group? I would like to be competitive but also need to be realistic (particularly at my age). I have been shooting with RWS Target Rifle and SK Rifle Match and not ready to splurg lots of $$ on Tenex or the like unless it is likely to make a huge difference.

Based on my scores, at this stage I am assuming that I need to improve my shooting skills before I start worrying about ammunition.

Cheers

David

[Tim S]

David,

you're pretty much at the point where selecting ammo becomes worthwhile. Selected ammo probably won't give you a 200 average (not unless your current ammo is really bad) but it should make a few points.

First point, selected ammo doesn't have to be top grade. Top grade ammo should be more consistent that cheaper grades, so you should have more chance of getting a really good match to your barrel, but cheaper grades can often shoot very well. Second grade ammo is often made to the same spec, and even on the same machinery as top grade, but you may need to test a few more batches.

Second, ammo testing is about knowing that your ammo will not just hold the bull, but also group tightly enough to give you some room for error in your aim. Not every brand, or even batch, will give much leeway, and some won't even hold the bull. Smallbore barrels are senstive to the vibrations created when the cartridge fires; some batches complement the barrel, and some don't. This is true for all brands and grades, no matter how expensive. I recently batch tested with Eley (Edge rather than Tenex); groups ranged from 13.8mm to 24.xmm (edge to edge) at 50m. This is with almost consectutive lot numbers of the same ammo. Obviously if I had picked up the 24mm batch at random, I would have been utterly frustrated by randon 9s (or worse) that I had called as good shots (this does sometimes happen). This batch is an extreme example, other batches would hold the bull, but the groups were so-so, either with fliers, or just a bit loose, so there would be little room for operator error. My chosen batch shot a neat round group with a good decimal score (316.8 over 30 shots).

Factory testing is popular here in the UK, as we have the Eley factory range, and Lapua and RWS also offer test facilities. Fcatory testing gives a wide range of ammuntiion, and usually electronic targetry, but many shooters will test at their home range too. You need a number of different brands and batches, the more the better. I'd ignore batches where with fewer than 1,000 rounds available to buy. A mechanical test rig is useful, but telescopic sights and a sandbag to steady your aim will work too.

Tim

[Cumbrian]

I can endorse Tim's points about batch testing. I had a nearly identical experience to his but with both RWS and Lapua at Bisley this year. And several batches of the most expensive RWS ammo actually performed worse, at least in my barrel, than one batch of their next best grade i.e. R50. A previous year one batch of Lapua's Centre X matched the best results obtainable, at least in my barrel, from their most expensive grade available for testing, Midas. So, batch testing need not result in the purchase of ammo that is excessively expensive. By the way, even the most securely clamped barrel is likely to perform better in the shoulder than on the test rig, so a group of 13mm or even 14mm is really excellent, even though a group of 13-14mm on an actual card would put you comfortably into the 9 ring. I'm a very average - or worse - club shooter but I buy only batch tested ammunition because then I know that I cannot blame the ammunition for poor results and must look even harder at my own shortcomings.

[bdutton]

ELEY has a test range in Winters TX (Killough Shooting Sports).

http://www.killoughshootingsports.com

You send them your barreled receiver and pay something like $40 to have them test every lot of ammo they have on hand for the line of ammo you prefer. 40 rounds per lot, usually more than 20 lots available. Thats 800-1000 rounds of testing! That includes the top of the line Tenex, followed by Eley Match (black box) and they are also offering the new Eley Edge for testing. Tenex is very expensive as is the Eley black buts its expensive for a reason. Edge is the least expensive of the match grade ammo that Killough is testing. The testing done is very scientific and better than anything you can do from a bench.

For $40+ shipping its a lot cheaper than buying 10-20 boxes of assorted ammo and then HOPE that there is enough of the best performing lot number still available to buy.

[Tim S]

...several batches of the most expensive RWS ammo actually performed worse, at least in my barrel, than one batch of their next best grade i.e. R50. ...even though a group of 13-14mm on an actual card would put you comfortably into the 9 ring....

Cumbrian,

R50 is RWS's top grade. R100 isn't a higher grade, it's R50 loaded to a slightly higher velocity, ostensibly for better performance at 100yards/metres.

I was testing at 50m not 25 yards; I've amended my post to show this. At 50m 13-14mm groups just overlap the 10-ring, but as scoring is inwards (i.e. best edge) will score all 10s if centred. 13-14mm edge to edge groups from a vice at 25 yards are unacceptable; I don't know if I've found ammunition this bad. Good ammunition should group much tighter, only just larger than calibre-sized; from memory my barrel grouped around 7mm (edge to edge) when I last tested at 25 yards.

[Bryan996]

There was another advantage to batch testing for me, I discovered that my 1813 barrel was knackered! I then bought a secondhand 1913 action and my scores instantly jumped up by a 2 point average. I would never have known otherwise.

[Cumbrian]

Tim,

You are right of course about the grades of RWS ammo. As regards the testing, it was done at 50 metres (unless it was yards - I never enquired) but I admit I do tend to think in terms of 25 yards, which is the distance I shoot at, which has the advantage of building in a safety margin when judging the results: 13-14mm at 50 metres must mean a much better result at 25 yards. I still think that shooting from the shoulder somehow improves on the results from a rigid test rig; I have seen some really bad fliers during the Bisley batch tests, which are not likely to have been the result of poor quality control in the production of top flight ammunition.

Another point about testing: RWS once put on an outdoor batch test at a local rifle club with a portable test rig, which was a complete waste of time because of exposure to wind and the lack of stability in the platform and vice. The groups were all over the place. I travelled nearly 50 miles there and back for nothing. I have confidence in what RWS and Lapua do at Bisley, however.

[Hemmers]

By the way, even the most securely clamped barrel is likely to perform better in the shoulder than on the test rig, so a group of 13mm or even 14mm is really excellent, even though a group of 13-14mm on an actual card would put you comfortably into the 9 ring.

What sort of card? The 10-ring of a 50metre ISSF target is about 10mm in diameter.
Eley's group sizes are outside edge* - so a 14mm diameter group from Eley would have every shot scoring comfortably inside the 10-ring. Even if they measured centre-to-centre of the shots, a 12-14mm group would put it's worst shots around 10.0, 9.9.

If you take the 10-ring as 10mm across, and a .22 round as 5.6mm across, then using outside-edge groups, the largest group where all shots were tens would be 5.6 + 10 + 5.6 = 21.2mm.
If you were using centre-to-centre groups, then 2.8 + 10 + 2.8 = 15.6mm.

*i.e. what is the smallest diameter circle you can fit all the shots inside of?

Having typed that, then I realised you may have been referring to 25 yards. A 13-14mm group is indeed no use to anyone at 25 yards. But since RWS, Lapua and Eley are in the business of winning Olympic Medals, their testing is all run at 50metres.

...several batches of the most expensive RWS ammo actually performed worse, at least in my barrel, than one batch of their next best grade i.e. R50. ...even though a group of 13-14mm on an actual card would put you comfortably into the 9 ring....

Cumbrian,

R50 is RWS's top grade. R100 isn't a higher grade, it's R50 loaded to a slightly higher velocity, ostensibly for better performance at 100yards/metres.

Not just slightly higher velocity, supersonic!
Okay, probably not that much faster in absolute terms as subsonics are not very far beneath the sound barrier, and R100 isn't usually very far over it, but enough that some ranges will get picky and not let you use it if they have steel plate backers or local noise restrictions.

But yes, it's not a higher grade - they're ostensibly equal.

R50 is the top-grade subsonic product, R100 is the top-grade supersonic product.

Understandably people get very confused and think that R100 is better because 100 is greater than 50. The RWS Branding is not very good - normally a company's flagship product is embodied in it's "Professional" range, but RWS's flagships (R50/100) are in the Premium Range. Meanwhile their budget training ammo is in the "Match" range. I assume they're called something else in German and the connotations embodied by those words are more appropriate. When they translate to English it doesn't make quite as much sense. The words Match, Premium and Professional could all be used to categorise their flagship product. Using all three of them tot title different lines, of which two are training and lower-grade ammo is just odd!

[BigAl]

By the way, even the most securely clamped barrel is likely to perform better in the shoulder than on the test rig, so a group of 13mm or even 14mm is really excellent, even though a group of 13-14mm on an actual card would put you comfortably into the 9 ring.

What sort of card? The 10-ring of a 50metre ISSF target is about 10mm in diameter.
Eley's group sizes are outside edge* - so a 14mm diameter group from Eley would have every shot scoring comfortably inside the 10-ring. Even if they measured centre-to-centre of the shots, a 12-14mm group would put it's worst shots around 10.0, 9.9.

If you take the 10-ring as 10mm across, and a .22 round as 5.6mm across, then using outside-edge groups, the largest group where all shots were tens would be 5.6 + 10 + 5.6 = 21.2mm.
If you were using centre-to-centre groups, then 2.8 + 10 + 2.8 = 15.6mm.

*i.e. what is the smallest diameter circle you can fit all the shots inside of?

Actually the ISSF 10 ring is 10.4 mm in diameter, and the bullet diameter is set to be 5.6mm, when using ISSF approved Electronic scoring systems. ISSF use 8mm scoring ring widths, so each scoring ring is 16mm larger in diameter than the one before. To keep this correct with decimal scoring, while using the inner-edge of the bullet for scoring the printed 10 ring has to become twice the ring diameter, less the bullet diameter. To calculate group sizes for decimal scoring you actually need to calculate the scores based in the position of the center of the bullet, as a couple of the higher decimals would otherwise need a negative sized scoring ring. This then gives a 10.9 ring with an error diameter of 1.6mm (0.0630") which would be the necessary CtC group size. To put that into the same EtE sizing that Eley are using at the test range then you would need to have a group of 7.2mm! To hold the score to 10.5 then you need to have a CtC group size of 8mm (.315"), or an EtE group of 13.6mm. To put those figures in perspective, I believe the best ever group size recorded during batch testing at any Eley customer range was bigger than 9mm, which would give you a 10.7 group, as 10.8 would need an 8.8mm CtC group.

Things are not as bad as they might seem though, as the group sizes that we are measuring, and discussing, are Extreme Spread. Group size should be normally distributed, and without seeing the figures I would hazard a guess that for most good groups, in the 10mm to 13mm EtE ES range the 90% confidence level should be about half the ES, so hopefully from your 13.6 mm (10.5) group around 90% of your shots ought to make it into the 10.9.

Alan

[higginsdj]

OK, that's going to require a special trip away for me (500km to the only/nearest location for that type of testing). Locally I can buy bricks or cases of 22LR of whatever type/brand the shop has in stock (only 1 shop in town and no, they will not special order unless I choose to buy a case of every batch I want to test) so no opportunity to batch test myself. (I should point out that in Australia ammo cannot be shipped, it has to be picked up in person - arrangements between dealers are somewhat different)

Is there something I can do myself with the ammo that I do have that can improve consistency? I know with my full bore ammo I reload using weight matched projectiles (+/- 0.1gn), cases (+/- 0.1gn) and drop powder to the nearest 0.02gn (1 kernel of powder) then weight sort the final product so I shoot them in decreasing weight order.

Cheers

David

[Tim S]

David,

there's nothing to stop you testing on your home range. Mechanical rigs and electronic targets make the test process a little easier (by eliminating some shooter error, and giving detailed information of the group afterwards), but aren't essential. As I wrote above testing is about confidence, the confidence that you are using the best ammunition that you can get. If you can only compare a few different brands/batches, you still get the best performer at the end. This is a good place to start, unless nothing that is available locally gives acceptable results when travelling may be worthwhile.

You can weigh and measure cartridges, but the consensus is that this gives very little (if any) benefit for an awful lot of bother. This is what factory QC is for, unless you are buying very low end ammo. Weighing may identify anomalous rounds, probably those that would have dropped low, but it won't change whether the ammo suits the barrel. Rim thickness and bullet concentricity are also measureable, but don't appear to have a big effect with a good quality rifle that has tight headspace and a tight match chamber.

Some high level shooters will use a barrel tuner (see http://shop.uptagrafftllc.com/Tuner-Tube-Tuner-Tube.htm and http://beesafeusa.com/beesting-tuner-bloop-tube/) to tighten groups, and even out some of the variations between batches. But these take time to set up, and pretty much require you to have good ammunition already, so probably aren't the answer until you are looking to scrape out the last point (or 0.1 points). Also tuners won't compensate for poor quality ammo, a knackered barrel, or for operator error. The weight may also change the balance of the rifle, making it quite muzzle heavy and requiring changes to the position.

[FrankD]

... so hopefully from your 13.6 mm (10.5) group around 90% of your shots ought to make it into the 10.9

Here comes an test report from the Eley testing range in Germany and shows an at that time new testing record. The test shows a 40 shoots test with an 13,4 edge to edge group. But even this outstanding grouping will give only four 10.9. Most shoots will give an score between 10.8 and 10.6, but there are also five 10.5 and three 10.4.

But this is an really outstanding grouping. The other shown groups on that testing report are also good and show much more what an average owner can expect from his rifle and barrel. And there is more spread in the given result. There are 10,1 and even a 9.9.

We have also to know, the grouping of the ammo and our own grouping (our faults) will always statistically add and decrease our results. This is true for an world class shooter and it is also true for an average or club shooter, also it has not the same importance. The influence increases much more if your scores increase.

So i would say, ammo testing is always important. It can help you to increase your scores, will give you more sureness and confidence and shows you the quality of your own rifle and barrel combo.


Last note: I have seen an ammo test with my own eyes with an otherwise real good barrel which gave only an average score of 95 for 10 shoots on the ISSF 50m target. Even Martynov couldn't shoot more than 570 with such an combo. The used ammo lot was one of the highest match products. There was nothing wrong with that rifle and there was also nothing wrong with that ammo lot. It was only the wrong combination and it is sometimes possible that you also get such a combo if you do not test.

I'm only a longtime club shooter but i can tell nearly every time the difference of a 12 - 14 mm grouping lot and an 18 - 20 mm grouping lot when i test this lots out of my shoulder in a blind test. And my Anni and Diana barrels are not really picky about different ammo lots.


Regards

Frank

[GaryD]

I would like to my comments about batch testing ammunition.
In February this year I went to the Eley factory in Birmingham in the UK and tested 24 different batches of Tenex.

To say I was surprised was an understatement, as the variations between the different batches was unbelievable, with the best 40 shot being 13.7mm and the worst 40.8.

Have a look at the print outs below and see what you all think.

The Group marked R50 was from a batch that I tested at Bisley in 2013 and was used as a reference to see if the Eley Ammunition could beat it.