Some .22 rim thickness measuring

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Re: Some .22 rim thickness measuring

Post by bladeracer » 29 Apr 2020, 4:32 pm

Rather than add the velocity data to separate posts I thought I'd just do a graphic of all the Eley.
Eley test velocities.JPG
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The CCI is the final fifteen rounds I finished the session with.
The Crosman is just some readings I took on the air-rifle with H&N Field Target Trophy while I was out.

Two shots went 1101fps and had a supersonic crack, the highest that did not go supersonic was 1098fps.

Statistical Deviation of 9fps for Tenex and Match, 10fps for Edge and CCI Std Velocity.
But 5fps for the .177" air-rifle surprised me, especially with the cheap H&N's.

I used the MTM rest for this test.
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The VisionKing 10-40x56 is a monster, but I haven't had any problems with it so far.
Very limited elevation adjustment so I had to shim the front ring .012" to be able to get a 50m zero for this testing.
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Re: Some .22 rim thickness measuring

Post by straightshooter » 01 May 2020, 7:21 am

bladeracer

For some reason after looking at your tactical peashooter I can't extirpate from my mind's eye the image of the host of the series Man vs. Food eating a 42 inch pizza with all the toppings.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 01 May 2020, 8:39 am

straightshooter wrote:bladeracer

For some reason after looking at your tactical peashooter I can't extirpate from my mind's eye the image of the host of the series Man vs. Food eating a 42 inch pizza with all the toppings.


Not being familiar with the show I don't know what that means, but I only see pizza about once a year, they don't deliver this far out of town :-)
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 Jun 2020, 12:27 pm

After a bit of a break I managed to get out for another session.
This time it was the Federal and Highland, a total of 364rds - 24 15rd mags, plus 5rds to empty a box.
I was sitting there for exactly two hours and my feet were frozen numb at the end, it was 9.4 degrees out there in the paddock, but at least there was no wind at all.
I have to say that I am getting a little sick of lugging the huge VK 10-40x56 around on the .22, looking forward to completing this and swapping the AR Optics back on.
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I forgot my original plan to shoot five 5rd groups for each type, I shot one 15rd mag of each this time. I also screwed up the chrono, for some reason I was convinced it held 200rd strings so I switched it midway through. Unfortunately, it only holds 100rd strings, so I lost some data. I may shoot those again in the next session.

One weird shot occurred with the Federal F712, I fired a clean shot but I couldn't find a hole in the target, must've gone through another hole. Then I spotted the damned hole five-minutes low and two-minutes to the right (the grid is 2MoA at 50m), what the hell! I _know_ the shot was good. The other two groups were terrible though (49mm and 73mm) so it was probably just four rounds clustered in 22mm in the top left of a group with the fifth at the extreme bottom right, making a 78mm group. This was some of the lost velocity data, but I didn't notice anything with the shot.
F712 dropped a shot.jpg
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And what $75 worth of holes looks like :-) Top left target is for CCI SV, 15rds to start the session (38mm, 22mm and 22.5mm), then 15rds between switching from the Federal to the Highland (11.5mm, 17mm and 31mm with a nasty flier - 11.5mm without the flier), then 20rds to end the test as a control (31.5mm, 21.5mm, 13.5mm, and 21mm to end the session), to monitor my own and the rifle's performance. If my shooting is falling apart during the session, the final control group should be significantly worse than the first control group. Again, I get the tightest group of the session with the CCI SV at 11.5mm.
20200611_165131c.jpg
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And the back of the 3mm MDF sheet after about 1500 bullets have passed through it, tons of life left in it yet, and only $8 at Bunnings.
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The CCI SV control target.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 Jun 2020, 12:56 pm

I started with the bulk Federal Auto Match.
The first group, at 21.5mm was looking good, but the next eight groups were not great, between 27mm and 50mm. These were batched by rim thickness but I'm not seeing any measureable difference between them. Velocity was 1157fps, ES 94fps, SD 22fps.
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Then we have the American Eagle HVHP (40rd boxes), nothing special at 33mm to 44mm groups. Velocity was 1212fps, ES 112fps, SD 32fps.
Then AE Suppressor with similar results. Velocity was 973fps, ES 61fps, SD 16fps.
20200611_173233b.jpg
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I had high hopes for the Federal F510, and it's good stuff, even cheaper than the CCI Std Velocity. Six groups around 20mm to 25mm, very consistent. Velocity was 1274fps, ES 48fps, SD 16fps.
20200611_173310b.jpg
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Then the F710 which shows some promise at 20mm to 33mm groups. Lost the velocity data :-(
F712 was pretty awful at 50mm to 75mm groups. Also no velocity data.
20200611_173501b.jpg
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F714 looks fairly consistent with 28mm to 36mm groups.
F724 was pretty awful at 35mm to 60mm groups.
20200611_173026b.jpg
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F711B started out with an excellent 13mm group, but opened up to an awful 48mm group.
F922B did similar with an 18mm group opening out to 42mm. Velocity was 1042fps, ES 39fps, SD 12fps. Very greasy though, horrible to handle.
20200611_172910b.jpg
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Then I fired three groups of CCI SV before switching to the Highland stuff.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 Jun 2020, 1:31 pm

Three groups of CCI SV shows no change in my shooting so it's onto the Highland.
I start with the RX HVHP which has always been pretty consistent for me, though not especially accurate. Groups from 21mm to 31mm. Velocity was 1287fps, ES 44fps, SD 12fps.
Then the RX Subsonic HP, also fairly consistent with 25mm to 34mm groups. Velocity was 1071fps, ES 82fps, SD 25fps.
20200611_172827b.jpg
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RX Target also shows excellent consistency with neat groups and no fliers, but around 18mm to 26mm for six groups. Velocity was 1178fps, ES 69fps, SD 17fps. All I can find when looking online is "Highland RX Target Standard Velocity 36gn Hollow Point", but they always have a picture of a box of "RX Target Solid Point". I have never seen the roundnose stuff, only the hollow point, and this stuff is definitely high-velocity. I can't explain it :-)
20200611_172644b.jpg
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The RX HVRN opens up a little bit to 19mm to 35mm groups. Velocity was 1266fps, ES 41fps, SD 14fps.
20200611_173346b.jpg
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Finally, the ZX Super Quiet lacks consistency, grouping 23mm to 54mm but with no pattern to the group. No velocity data unfortunately, but definitely subsonic. It's supposed to run 840fps. The VK has a dual retical with a second crosshair 5MoA below the centre one. I expected the ZX to drop significantly so I held on the lower crosshair, but was surprised to see very little drop at all.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 Jun 2020, 1:41 pm

I haven't cleaned the bore since I started this test on March 24th so we now have 1272rds down the tube of 39 different types.
It is still grouping well within the realm of what it was grouping after a thorough clean at the start (19mm, 17mm and 16mm were the first three groups), so I'm not yet ready to clean it.
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Re: Some .22 rim thickness measuring

Post by rc42 » 28 Jul 2020, 4:43 pm

Thanks for posting all of this, it was an interesting read.

I just got myself a reasonable digital caliper, a Kincrome from Bunnings that claims to measure accurately below 0.001", some digital scales that measure 0.01g and I have a Hornady rim thickness guage on the way so I'll be repeating some of what you've done here and sorting Eley Standard bulk into batches to see if I can improve grouping at 50m

The ammo will be used for prone target shooting onto electronic targets and my rifle already groups well with the budget bulk Eley ammo but still suffers from regular fliers and odd changes in group size from one series of 10 to the next. I don't want to train with better ammo at 2 or 3 times the price so I'm hoping that sorting will be enough.

I have around 8,000 rounds of Eley bulk but will start with just a few hundred, sorting by rim thickness and then secondary sorting by weight until I have a number of closely matched batches that I can shoot groups with. I don't have a chronograph but my barrel tuner claims to compensate for small differences in muzzle velocity so it will be interesting.
The Eley use a hard parafin wax coating so sticky fingers and gunge should be minimized, I'll post back when I have some results.

I've been looking for a 22LR projectile resizing die too but they don't seem to exist in Australia and are even difficult to find elsewhere, if I can get one that will be my next phase.
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Re: Some .22 rim thickness measuring

Post by marksman » 28 Jul 2020, 4:50 pm

l second that blade, very interesting thanks for going to the trouble posting it all up :drinks:
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Re: Some .22 rim thickness measuring

Post by bladeracer » 29 Jul 2020, 4:56 pm

I've gotten a little distracted lately but I'll get back to this soon I hope.
While I don't consider a chronograph to be essential, for the price I do find it very useful. I haven't seen a distinct improvement in accuracy due to tighter Standard Deviation or Extreme Spread, so I don't agree with trying to develop accurate loads just from velocity data, or in chasing smaller SD or ES on the chronograph, I just chase smaller groups on the target. For a large-scale test as you're planning, with hundreds of rounds and likely dozens of hours, I really would invest in a chronograph. I'm on my second ProChrono Digital and haven't found it lacking in any way. I just checked Ebay though and I see the dollar's collapse has them up around $350 currently.

I keep meaning to make a .22LR bullet swaging die but never manage to get around to it, one day :-)


rc42 wrote:Thanks for posting all of this, it was an interesting read.

I just got myself a reasonable digital caliper, a Kincrome from Bunnings that claims to measure accurately below 0.001", some digital scales that measure 0.01g and I have a Hornady rim thickness guage on the way so I'll be repeating some of what you've done here and sorting Eley Standard bulk into batches to see if I can improve grouping at 50m

The ammo will be used for prone target shooting onto electronic targets and my rifle already groups well with the budget bulk Eley ammo but still suffers from regular fliers and odd changes in group size from one series of 10 to the next. I don't want to train with better ammo at 2 or 3 times the price so I'm hoping that sorting will be enough.

I have around 8,000 rounds of Eley bulk but will start with just a few hundred, sorting by rim thickness and then secondary sorting by weight until I have a number of closely matched batches that I can shoot groups with. I don't have a chronograph but my barrel tuner claims to compensate for small differences in muzzle velocity so it will be interesting.
The Eley use a hard parafin wax coating so sticky fingers and gunge should be minimized, I'll post back when I have some results.

I've been looking for a 22LR projectile resizing die too but they don't seem to exist in Australia and are even difficult to find elsewhere, if I can get one that will be my next phase.
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Re: Some .22 rim thickness measuring

Post by rc42 » 01 Aug 2020, 12:46 am

Hornady rim thickness gauge arrived this afternoon so I spent much of the afternoon and evening working through a few boxes of Eley Std bulk.
The rim thickness seems to match previous shooting results, picking rounds from the box there will be between 5 and 20 of nearly the same rim thickness, then one way off and a couple somewhat near, hopefully the sorted batches will shoot more consistently and group better.
The rounds give a slightly different result if rotated but are generally within 1 thou and I have grouped them on the thickness in thou measured in half thou increments as reported on the caliper.

Thickness and number of rounds so far in that group are as below:

34.0 54
35.0 13
36.0 3
37.0 30
37.5 102
38.0 296
38.5 620
39.0 538
39.5 140
40.0 47
41.0 9
42.0 46
43.0 26
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Re: Some .22 rim thickness measuring

Post by bladeracer » 01 Aug 2020, 2:26 am

rc42 wrote:Hornady rim thickness gauge arrived this afternoon so I spent much of the afternoon and evening working through a few boxes of Eley Std bulk.
The rim thickness seems to match previous shooting results, picking rounds from the box there will be between 5 and 20 of nearly the same rim thickness, then one way off and a couple somewhat near, hopefully the sorted batches will shoot more consistently and group better.
The rounds give a slightly different result if rotated but are generally within 1 thou and I have grouped them on the thickness in thou measured in half thou increments as reported on the caliper.

Thickness and number of rounds so far in that group are as below:

34.0 54
35.0 13
36.0 3
37.0 30
37.5 102
38.0 296
38.5 620
39.0 538
39.5 140
40.0 47
41.0 9
42.0 46
43.0 26



Wow, you are seeing very different results to mine, although I only measured a single box, which may be an anomaly. I'll have a closer look at your numbers tomorrow.

Have double-checked many to confirm you are getting consistent measurements, turning the round to take several measurements to find the thinnest part of the rim?
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Re: Some .22 rim thickness measuring

Post by bladeracer » 01 Aug 2020, 6:05 pm

Comparing your figures with mine.
I only measured one box, 355rds.
BR Eley Standard Batching.JPG
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You measured four boxes, 1924rds, a far more relevant sample.
RC42 Eley Standard Batching.JPG
RC42 Eley Standard Batching.JPG (45.63 KiB) Viewed 8142 times


Yours spread across .009", mine across only .006". Mine measure from .031" to .037", and all but two rounds are from .032" to .036", but that could simply be due to my smaller sample. It's odd that using identical equipment you are measuring in a higher range than mine, probably just due to technique, yours are in the .034" to .043" range. Having so many more samples at the higher end though leaves me wondering if they might not fall into smaller batches when measured again.

I very regularly pulled rounds from batches I'd already measured and measured them again to confirm they were correct. And all of the smaller batches I measured again and found almost all of them actually measured smaller than my first measurements. This is why it is vital to turn the cartridge several times to ensure you are finding the smallest possible measurement of the rim. It is also very important to regularly clean the anvil and the chamber as lube residue builds up fairly quickly. The brass rim is not manufactured to half-thou precision, in my opinion, even .001" might be stretching it, and I think anything under .002" difference between cartridges is irrelevant at the target, from what I've seen. I did find that the consistency of thickness around the rim on Eley ammo is better than many of the other brands though.

Overall, I think we can see a similar pattern in consistency of manufacture, both our data show about 90% of them to be within .003". I didn't see any measurable difference in group size though. I fired one group taken from the extreme outliers of my sample (one at .031", two at .032", one at .036" and one at .037"), and the group was better than most of the batched groups, and only bettered by one group of .034" batched.

As you have 80rds in your extreme batches you could shoot groups with each, and with these two batches mixed, and see if there's a difference.

I'm thinking that due to the consistency of manufacture of the higher-quality ammo, the rim thickness/primer distribution is far less relevant than the bullet itself.

I consider Eley Standard to be the very worst of an exceptional manufacturer (most of their ammo measures within .001", throughout the entire batch), by a very wide margin, though still better than many other brands' best stuff. I would assume they take the brass that is rejected from their other lines, and use it to make this bulk ammo, but it is still very good. Assuming they do the same with their bullets, I think the weight, balance and symmetry of the 40gn bullet plays a bigger role in results at the target. Any production line that can turn out millions of rounds with consistently-measured 1gn powder charges can probably be relied upon for very consistent bullet weights also, so bullet diameter and shape are the best targets to address I think.

Looking forward to seeing more results!
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Re: Some .22 rim thickness measuring

Post by rc42 » 02 Aug 2020, 6:06 pm

Had another sorting session today and stopped when I was only a little past the point of wishing I'd never started.
Got through another two bulk boxes with just over 500 in each, I think they add a few to the stated 500 to avoid making false claims.

Anyway, cumulative sorted boxes now contain the following:
34 78
35 23
36 3
37 31
37.5 113
38 443
38.5 1050
39 823
39.5 200
40 58
41 13
42 64
43 33

The two boxes were from different batches but the numbers were close so may have been the same day (3117 30323) and (3117 30335), the first of those had mostly 38-39 and the second was mostly 38.5-39.5, it seems that using boxes from different batches is skewing the results somewhat in terms of what a purchaser of one box (or even case) should expect. It seems reasonable that other batches would be centered around the 34-35 thickness as bladeracer's were.

I manged to shoot one 60 shot practice match with sorted 38.5 rim thickness and there did seem to be fewer wide flyers but the wind was a little too gusty to be sure, it will certainly be interesting to see what the rifles does with the different rim thicknesses but that's going to take some time.

Sorting rim thickness certainly won't turn practice ammo into high end match ammo and my ability is also a limit on the testing but I'm hoping to get some meaningful results in regard to improved grouping eventually.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 02 Aug 2020, 6:50 pm

rc42 wrote:Had another sorting session today and stopped when I was only a little past the point of wishing I'd never started.



I remember that feeling well :-)
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Re: Some .22 rim thickness measuring

Post by rc42 » 03 Aug 2020, 9:31 am

A few notes to anyone else following this crazy path.

The Hornady rim thickness gauge isn't the best quality, the plate that the rim sits against during measurement isn't flat so the actual measurement is taken between the top of the rim and some point off center on the back of it, because of the stamped logo this makes it very prone to changes in measurement as the round is rotated.
I put the plate onto a flat grindstone and the picture shows how the high point was removed from it until the stone was touching the entire face, the additional scratches are from measuring 3,000 rounds.

The alignment against the tube that holds the round also needs some tweaking, I pushed them together with some fine grade abrasive paper between them which I then pulled out to get the top of the tube to sit completely flat against the back plate. By doing this first rotating the rounds often made no difference to the measurements but worst case was about 0.001" variation. This helped speed things up as I eventually moved to single measurements on each round unless they were extremes or the display was flapping between measurements.

Eley Standard is parfin wax lubricated so doesn't have the oily gunking up problem of other types but still needed cleaning every 30-50 measurements using a cotton bud with some G96 on it.
I have another 5,000 rounds still boxed but I'm not going to measure further, I have plenty of sorted rounds for testing and it's going to take me months to put those downrange and try to identify any meaningful benefit to the sorting process.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 03 Aug 2020, 11:10 am

Don't lose sight of what it is that we're measuring, both the precision of measurement required, and the precision of the manufacturing process. .22LR rims are not turned on a lathe, they are punched out of enormous sheets of brass at rates of many thousands per hour, all the time rolling around in huge piles, and being spat from one process to the next at speed.

And I don't believe we need to batch them down to even one-thou variations, I would think even .1mm (or .004") would be sufficient. We could batch them down to ten-thous, but virtually every batch would have just a handful of rounds in it, with most of your ammo being discarded for excess thickness variation around the rim. Then we find that twenty to thirty batches all shoot identically on the target - meaning they could all have been batched together anyway.

All we're trying to do is weed out the extreme anomalies in an attempt to reduce fliers.

Some of the ammo I measured had several thou variation around the rims, but Eley does not, at least outside of their bulk offering.
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Re: Some .22 rim thickness measuring

Post by rc42 » 03 Aug 2020, 10:34 pm

Had a fun shooting session at the range this evening after some sighters I shot 6 groups of 10 sorted rounds onto electronic targets, almost no wind so variations were down to myself, flyers and the different rim thicknesses.

I shot batches 34, 37, 38, 39, 40, 42, corresponding scores were 98.4, 96.8, 99.3, 101.8, 100.8, 95.2
Grouping in the 38-40 range was noticeably better than the smaller or larger extremes but all groups still had flyers except the 34 which helped the score despite otherwise poor grouping.

Following that I shot a full 60 shot match with a 38.5 batch, scores were 99.7, 98.8, 95.7, 100.2, 99.2, 100.8
Total score was 594.4 which is actually the second best result I've ever got from Eley Std ammo (by about 1 point) and the main loss of points were those dammed flyers that I know weren't my fault, clearly the bad flyers aren't caused by rounds with a different rim thickness.

Testing will continue, I have nearly 3,000 sorted rounds and batching by rim thickness does seem to have improved things but cheap bulk ammo has a lot of flyers whilst expensive match grade ammo has very few. Hopefully sub-sorting by weight with further improve grouping.

Interestingly the Tenex that I have measures at 39 rim thickness, which my rifle really likes, with about a dozen measured showing almost no variation in rim thickness or weight.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 03 Aug 2020, 11:47 pm

I got very good improvement when I first did this with Remington Cyclones, virtually halving the group sizes. But I specifically used the lowest quality I could get so any improvement would be very obvious, and it was. I doubt the difference in higher quality ammo is anywhere near as significant.

I'll have to pull my finger out and make a bullet swaging die.
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Re: Some .22 rim thickness measuring

Post by rc42 » 04 Aug 2020, 2:30 pm

Interesting read here where the overall conclusion seems to be that rim thickness and weight sorting does not produce statistically significant results
https://www.thehighroad.org/index.php?t ... cy.850634/

This article in particular mentions some of the metrics used by Eley and suggests what really matters but mere mortals won't be able to make those measurements.
http://www.nielsonbrothersarms.com/22%2 ... ricity.htm


I'll just keep shooting my already sorted ammo and see if the initial results were a genuine improvement or just luck
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Re: Some .22 rim thickness measuring

Post by bladeracer » 04 Aug 2020, 2:51 pm

Yes, I tried weight batching and saw no measurable improvement, even with low-quality ammo. As I said earlier, if they can turn out ammunition with miniscule 1gn charges with incredible consistency, I think .22LR manufacturers are well on top of weight variation controls.
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Re: Some .22 rim thickness measuring

Post by Wyliecoyote » 11 May 2021, 6:44 pm

A lot of work there bladeracer. The benefit of competing in rimfire benchrest in the heyday of BR and Hunterclass is that one quickly learns what works in rimfires. Generally a quality barrel, match chamber where the rifling engages the bullet a grease ring or more, an action with a repeatable firing strike and finally the mystery batch of ammo. Anyone who has tinkered in this area can tell you rim thickness gauges are good at finding poor ammunition and are possibly unmasking the real issue of erratic ignition. But if used should be made from a portion of the barrel offcut and made with the same reamer the chamber was cut with. Weighing cartridges is an exercise in futility simply because you never know what discrepancies you are actually weighing. Light charge heavy bullet, heavy charge light bullet, primer mix or the case itself.
With rim thickness and factory head space, this is set around 44 thou to cover every possible breed of ammo. Some like Brno and 541s are around 42 thou.
Eley Tenex rims once measured about 41 thou when placed into a freshly cut chamber and measured with a depth gauge. So the head space on match rifles would be set at zero or more generally a half a thou crush on that 41 thou. But should you try to use something like Federal or SK or even some Lapua, the bolt may not close. Too bad if you got a poor performing batch of Tenex which was the case in the 90s. So yes this is all pretty unrealistic for a plinking rig but when you combine the 44 thou and then some, a rather generous chamber ID and feed chamfer cut, the bullet seated a mile off the lands, the chances of getting a shooter diminishes and feeding such rifles ammo like Tenex is like feeding strawberries to pigs..
Herein lies the problem with buying over the counter. PWS rifles for example are very hit and miss for accuracy. The bolt rim recess is around 44 thou. Some are deeper. Some settle for what they get, sell it off or choose to have it remedied because it doesn't shoot like the one on youtube. You can set the tenon length with infinite combinations of the factory offered barrel shims and still do no better than a loose 44 thou at absolute best. All you achieve is a smashed toggle bearing when an unknowing gunsmith tries to close the headspace too much and gets that toggle to snap shut. They are not meant to be forced, but operated by a solitary finger. Hence some of them never shoot to their potential or advertised hype. The bolt face, as Volquartsen now does (same action), must be machined to shallow the recess and get the front face off the back of the tenon, another major killer of accuracy.
Many factory rifles are set up on this loose standard, but a few like T1x, Quad and P94s, Anschutz BR50 etc are able to set headspace for any brand of ammunition by a barrel clamp arrangement. All have excellent ignition, a major factor in good rimfire accuracy, and all have barrels approaching custom grade.

With testing ammunition. Every brand uses different lubricants from grease, wax and mica and combinations of each. At no time is it advisable to shoot different lube based ammunition without cleaning between when looking for accuracy. You will get erratic results like a spectacular group that will never repeat, to shot patterns and everything in between. If you don't clean the bore, especially the throat, free of another brands lubricant and that dreadful crushed glass used in the primer mix, you are literally pissing in the wind. Yep it may take 5, 10 or even 20 rounds to prime the bore, but the test result will be real. The wives tale of never cleaning a rimfire is very quickly dispelled when one goes to any major benchrest match. Some barrels need long intervals, some shorter. But they are all cleaned.

What i always suggest to those who ask is buy to the objective you are happy with with both rifle and ammo. Clean the barrel and shoot the entire 50, foulers and all into groups of 5, 10 or whatever. By then you will see a pattern of groups from one barrel state to the other. If possible do it over a chrono to see if it correlates to velocity spread equals erratic groups. Note that 20 fps variance is worth 0.25" of vertical dispersion at 50 meters on ammo rated at around 1070 fps. Ammo with this capability or better is usually limited to the top end of the spectrum like Tenex, Black Match, Lapua X-act etc.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 12 May 2021, 6:25 pm

Yes, a lot of time went into it, and it only got started because I was recovering from illness. Very difficult to commit such time to these things when I'm healthy :-)

To me, Benchrest is more a science project than enjoyable shooting :-)

As I'm not interested in competition, I have no interest in competition rifles designed to excel on paper, I just enjoy actually shooting, whether hunting, plinking, or simply experimenting.

I resolved to find out for myself precisely which ammunition performed consistently the best for me in my rifles. I spent many, many hours researching all the types of ammo available in Australia, then I had my dealer get me everything he was able to. I also ordered a bunch of stuff online and made a trip up to Dandenong to collect it. The rest I ordered online and had delivered, several times as stock became available. I ended up with 100 different types of ammo, there are a handful of types I still have not been able to get my hands on. I still keep stock of those 100 types for testing in other rifles.Some of it was bulk ammo, a lot of it I ordered bricks to make life easier for my dealer. From memory it was a total in excess of 40,000rds, and cost me something north of $7000. Some of the exotic stuff was 70-cents per round (plus freight), the cheapest stuff I paid 7-cents apiece at $34/500rds on special.

Having tested most of this ammo in several rifles now, I've found that very few types behave badly, or differently, being fired in a bore coated with another type's lube, and the few that do, come good within 10-20rds or so anyway. If I found ammo that only performed well in a clean bore, it'd be useless to me, particularly when there are so many other types that allow me to enjoy shooting for 800-1500rds before accuracy starts to degrade and cleaning is required.

I also haven't seen a direct correlation between ES and accuracy (rimfire or centrefire), a few types give me SD in single digits, like CCI Standard Velocity, Tenex and Eley Edge, but other stuff with ES of 60 or more can shoot equally well, or better, like SK High Velocity (ES is a 5% velocity difference - with groups half the size of Tenex), or SK Rifle Match.

As far as I'm concerned, the only indicator of consistent accuracy comes from lobbing bullets at paper and measuring the result, not the velocity.



Wyliecoyote wrote:A lot of work there bladeracer. The benefit of competing in rimfire benchrest in the heyday of BR and Hunterclass is that one quickly learns what works in rimfires. Generally a quality barrel, match chamber where the rifling engages the bullet a grease ring or more, an action with a repeatable firing strike and finally the mystery batch of ammo. Anyone who has tinkered in this area can tell you rim thickness gauges are good at finding poor ammunition and are possibly unmasking the real issue of erratic ignition. But if used should be made from a portion of the barrel offcut and made with the same reamer the chamber was cut with. Weighing cartridges is an exercise in futility simply because you never know what discrepancies you are actually weighing. Light charge heavy bullet, heavy charge light bullet, primer mix or the case itself.
With rim thickness and factory head space, this is set around 44 thou to cover every possible breed of ammo. Some like Brno and 541s are around 42 thou.
Eley Tenex rims once measured about 41 thou when placed into a freshly cut chamber and measured with a depth gauge. So the head space on match rifles would be set at zero or more generally a half a thou crush on that 41 thou. But should you try to use something like Federal or SK or even some Lapua, the bolt may not close. Too bad if you got a poor performing batch of Tenex which was the case in the 90s. So yes this is all pretty unrealistic for a plinking rig but when you combine the 44 thou and then some, a rather generous chamber ID and feed chamfer cut, the bullet seated a mile off the lands, the chances of getting a shooter diminishes and feeding such rifles ammo like Tenex is like feeding strawberries to pigs..
Herein lies the problem with buying over the counter. PWS rifles for example are very hit and miss for accuracy. The bolt rim recess is around 44 thou. Some are deeper. Some settle for what they get, sell it off or choose to have it remedied because it doesn't shoot like the one on youtube. You can set the tenon length with infinite combinations of the factory offered barrel shims and still do no better than a loose 44 thou at absolute best. All you achieve is a smashed toggle bearing when an unknowing gunsmith tries to close the headspace too much and gets that toggle to snap shut. They are not meant to be forced, but operated by a solitary finger. Hence some of them never shoot to their potential or advertised hype. The bolt face, as Volquartsen now does (same action), must be machined to shallow the recess and get the front face off the back of the tenon, another major killer of accuracy.
Many factory rifles are set up on this loose standard, but a few like T1x, Quad and P94s, Anschutz BR50 etc are able to set headspace for any brand of ammunition by a barrel clamp arrangement. All have excellent ignition, a major factor in good rimfire accuracy, and all have barrels approaching custom grade.

With testing ammunition. Every brand uses different lubricants from grease, wax and mica and combinations of each. At no time is it advisable to shoot different lube based ammunition without cleaning between when looking for accuracy. You will get erratic results like a spectacular group that will never repeat, to shot patterns and everything in between. If you don't clean the bore, especially the throat, free of another brands lubricant and that dreadful crushed glass used in the primer mix, you are literally pissing in the wind. Yep it may take 5, 10 or even 20 rounds to prime the bore, but the test result will be real. The wives tale of never cleaning a rimfire is very quickly dispelled when one goes to any major benchrest match. Some barrels need long intervals, some shorter. But they are all cleaned.

What i always suggest to those who ask is buy to the objective you are happy with with both rifle and ammo. Clean the barrel and shoot the entire 50, foulers and all into groups of 5, 10 or whatever. By then you will see a pattern of groups from one barrel state to the other. If possible do it over a chrono to see if it correlates to velocity spread equals erratic groups. Note that 20 fps variance is worth 0.25" of vertical dispersion at 50 meters on ammo rated at around 1070 fps. Ammo with this capability or better is usually limited to the top end of the spectrum like Tenex, Black Match, Lapua X-act etc.
Last edited by bladeracer on 13 May 2021, 4:02 pm, edited 1 time in total.
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Re: Some .22 rim thickness measuring

Post by Gamerancher » 13 May 2021, 8:27 am

"As far as I'm concerned, the only indicator of consistent accuracy comes from lobbing bullets at paper and measuring the result, not the velocity." bladeracer.

Gee, sounds a lot like benchrest :sarcasm:
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 May 2021, 8:50 am

Gamerancher wrote:"As far as I'm concerned, the only indicator of consistent accuracy comes from lobbing bullets at paper and measuring the result, not the velocity." bladeracer.

Gee, sounds a lot like benchrest :sarcasm:


It is similar, just without the driving force of needing all the bullets to go through the same hole, week after week after week :-)
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Re: Some .22 rim thickness measuring

Post by Gamerancher » 13 May 2021, 8:57 am

"all the bullets to go through the same hole, week after week after week"
Wouldn't that actually be the ultimate indicator of accuracy then? :unknown:
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 May 2021, 10:16 am

Gamerancher wrote:"all the bullets to go through the same hole, week after week after week"
Wouldn't that actually be the ultimate indicator of accuracy then? :unknown:


It would be if that was your goal in shooting. I only need a test result.
My point is that you can't use other things, like velocity, to determine whether a load is accurate.
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Re: Some .22 rim thickness measuring

Post by Larry » 13 May 2021, 10:39 am

My take away from all the testing that has been done and the results is that the more expensive ammo is generally made to a more consistent spec. Hence you are paying for someone else to do all the sorting work and in turn give you more consistent results. No way I am buying a big bucket of cheap 22 and then sitting down for a day measuring rim thickness and sorting several thousand bullets.

Your point is valid BR velocity on its own can not determine a accurate load. However I would say that a wide ES is a good indication that the load will not be accurate. Simple ballistic math supports that.
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Re: Some .22 rim thickness measuring

Post by Wyliecoyote » 13 May 2021, 12:02 pm

"Your point is valid BR velocity on its own can not determine a accurate load. However I would say that a wide ES is a good indication that the load will not be accurate. Simple ballistic math supports that."

At 50 meters with a rimfire that first part is sort of true. But double that or extend it to 200 meters in the case of those that inflict self harm shooting Rimfire Fly or in PRS that i only shoot rimfire in these days, and it becomes apparent very quickly how important ES becomes.
To further that point one has to believe that positive compensation exists to think that a good group of high ES at 50 meters equals good group at a 100 meters. Not possible with a rimfire where Merril Martin of Precision Shooting magazine proved back in the mid 90s shooting through mutiple screens.
This is why i stated to fire the whole box of 50 rounds while testing because it is possible through the mathematical theory of permutations and combinations to luck out and pick five cartridges that deliver a spread of under 20 fps ES and give the one off quarter inch group at 50 meters. The same mathematics says it won't happen again. That is why the chronograph is employed to see if it is velocity that destroys the group. From there if the velocity is constant but the group is erratic at times, that is when the tuners on rimfire rifles come into their own.

Below is an example of 2 rimfires i own shooting at 75 yard zero i use for my PRS settings. Top is the PWS no tuner using the same very good ES batch of CCI standard. Bottom rows are tuners settings on my T1x fitted with a tuner that utilises the existing 1/2" x20 TPI threads. The ES tested over a chrono had a spread of under 25 fps. You can clearly see the tuner close the vertical as it is wound out looking for the sweet spot. You cannot do this with something that runs around 50 fps no matter what the rifle. Without the tuner at 50 meters the T1x holds under a half inch with the CCI, not as good as RWS or Eley Match, but with the tuner it holds 0.3", and rivals the other two. But they do it without the tuner and both run an ES of under 20 fps with some batches well under that.
All that has been done to the Tikka is the tuner added and headspace set at zero and trigger lightened.
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Re: Some .22 rim thickness measuring

Post by bladeracer » 13 May 2021, 4:14 pm

My ES figures listed were generally taken over 25rds, five 5rd groups (just my preference as it lets me do this test twice per 50rd box of ammo). A few were only three 5rd groups due to lack of ammo, some were over 50rds, up to several hundred rounds (in the case of CCI Standard Velocity, Eley Edge, Tenex, and much of the bulk ammo that I have heaps of (so I shoot fairly it regularly). I shoot more CCI SV than anything else as I buy it by the case.

Highland RX HVHP has an ES of 12fps, but doesn't group much better than 2-minutes, though it does shoot those groups pretty reliably. I picked up a lot of bricks of all the Highland ammo, it's a good choice for cheap Metallic Silhouette practice, though not in my levers, the blunt bullet doesn't feed great in my levers. Highland RX HVRN has ES of 12fps. Federal F510 has ES of 16fps. Federal AutoMatch bulk has ES of 22fps but shoots very poorly. CCI SV has ES of 40fps and outshoots all but two other types of ammo, one of which has ES of 56fps.

I disagree that you can decide which ammo will be accurate based on the mathematics of velocity, while ignoring the mathematics of variations in bullet weight and shape, case volume, and priming compound charge and distribution, as well as the variation in the dimensions of the brass itself.

I just ran CCI SV through a ballistics calculator, the difference in elevation at 50m between 1080fps and 1060fps (SD of 10fps, ES of 20fps) is .15" or less than 4mm. That's less than the group size variation, thus the bullet may be travelling 15fps slower or faster, but that does not guarantee it'll drop or rise. It can be faster but hit lower, or be slower and hit higher, due to the other variations in the total dynamic of the shot, including the rifle itself.


Wyliecoyote wrote:"Your point is valid BR velocity on its own can not determine a accurate load. However I would say that a wide ES is a good indication that the load will not be accurate. Simple ballistic math supports that."

At 50 meters with a rimfire that first part is sort of true. But double that or extend it to 200 meters in the case of those that inflict self harm shooting Rimfire Fly or in PRS that i only shoot rimfire in these days, and it becomes apparent very quickly how important ES becomes.
To further that point one has to believe that positive compensation exists to think that a good group of high ES at 50 meters equals good group at a 100 meters. Not possible with a rimfire where Merril Martin of Precision Shooting magazine proved back in the mid 90s shooting through mutiple screens.
This is why i stated to fire the whole box of 50 rounds while testing because it is possible through the mathematical theory of permutations and combinations to luck out and pick five cartridges that deliver a spread of under 20 fps ES and give the one off quarter inch group at 50 meters. The same mathematics says it won't happen again. That is why the chronograph is employed to see if it is velocity that destroys the group. From there if the velocity is constant but the group is erratic at times, that is when the tuners on rimfire rifles come into their own.

Below is an example of 2 rimfires i own shooting at 75 yard zero i use for my PRS settings. Top is the PWS no tuner using the same very good ES batch of CCI standard. Bottom rows are tuners settings on my T1x fitted with a tuner that utilises the existing 1/2" x20 TPI threads. The ES tested over a chrono had a spread of under 25 fps. You can clearly see the tuner close the vertical as it is wound out looking for the sweet spot. You cannot do this with something that runs around 50 fps no matter what the rifle. Without the tuner at 50 meters the T1x holds under a half inch with the CCI, not as good as RWS or Eley Match, but with the tuner it holds 0.3", and rivals the other two. But they do it without the tuner and both run an ES of under 20 fps with some batches well under that.
All that has been done to the Tikka is the tuner added and headspace set at zero and trigger lightened.
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