Average velocity is not the problem.
Velocity differences cause vertical spread.
Cartridge imperfections and differences in assembly
result in dispersion in any direction, relative to
the orientation of the cartridge when chambered.
On a scoped rifle, barrel length has minimal effect
on accuracy. Barrel quality is more important.
I have an 18 inch Shilen that produces better results
than my 21 inch Lilja. My factory 20" 455 Varmint barrel
has problems and has trouble staying under 0.6 inch spread at 50 yards.

In order to produce predictable trajectories,
everything must be/happen almost exactly the same
every time the trigger is squeezed. Any differences,
affects the bullet's trajectory and changes it's flight path.

Any movement of the barrel/receiver relative to the stock,
shifts in support of the setup, atmospheric changes,
mechanical slop is going to degrade accuracy.


Stop believing that the labeled velocity means anything
in regards to what you obtain with your rifle.
Labeled velocity can be based on design specifications
or the averaged measured velocity of the cartridges fired
during batch testing at the factory, from multiple barrels
and different temperatures/humidities/elevation at the factory.
Conditions, elevation at your location will affect burn rate.
That will change cartridge velocities, as will chamber dimensions,
bore diameter and bore surface finish.

Stop blaming supersonic transition for loss of accuracy.
That is an internet fallacy, disproven by ballistics studies
and results documented and posted on multiple occasions.
The 22lr is not a tail heavy, long, slender projectile.
Totally different behavior in the transonic zone.

The cause of poor accuracy with hi-v 22lr
is due to poorly made cartridges. Cheap ammo
handled roughly during manufacture with sloppy tolerances
will result in sloppy trajectories no matter what the labeled velocity.

 

Thank you for your response, I understand what you are saying about the labeled velocities. That is why I have learned to chrono them.
But why the difference in velocities between the two actions when everything else is the same?

These are sample sizes of at least 25 -50 rounds through the same chrono on the same day. As I had mentioned the Right hand Action is new and feels tighter. I measured it but to but I wasn't as absolute about the numbers by remeasuring several times so I could be in error.
Could a few thousands tighter / looser action make a difference in the velocity or accuracy?

I did measure the rim thickness between the Target and Club. I forget the #s but they are grouped consistently by the different rim thickness and overall weight.

The velocity for the Eley Target Average is 1130 for the Right Hand Action and 1090 for the Left Hand Action
The velocity for the Eley Club Average is 1098 for the Right Hand Action and 1085 for the Left Hand Action.

Also, I am still trying to nail down the Action Torque on the new Right Hand Action. I do think that may be playing a part in the lack of consistency of my grouping. Groups are in general sub MOA but erratic in pattern. One will be near one hole, the next will be spread all over the place.

 

I think I got lost in the descriptions.

Which barrel is in which action?
The individual barrel used is the likely reason
for average velocity difference.
Barrel length, bore finish, bore diameter,
chamber dimensions will affect muzzle velocity.

Rimfire ammunition is not particularly uniform in components, chemistry, assembly or quality.
Those differences in each cartridge cause the trajectories to vary.

Sorting rimfire cartridges by weight, rim thickness,
brass dimensions, bullet dimensions is not useful.
I've tried it. 500 cartridges at a time. 4 times.
It gives you something to do and keeps you occupied,
but does not relate to predictable accuracy.
A rimfire cartridge is a system of components,
chemistry, assembly, tolerances and attention to detail.
All vary moment by moment on the assembly line.
No two cartridges are identical. No two boxes,
bricks, cases or lots either. Mass produced ammo
is not able to achieve the uniformity in production,
necessary for the cartridges to behave as we would like.
Too many differences, too many variables, for sorting to be effective.
Sorting is useful only to optimists.


Eley Club and Eley Target are for use when results are unimportant.
Bottom grades of the cartridges made by Eley.
Not expected to be used when accuracy is critical.
For offhand use and distances less than 100 feet, they're adequate.
For precision target shooting, 50 yards,
an inch of spread is no surprise.

Your expectations are unrealistic, using those cartridges.

Linked below are the results from several years of entertainment.

50 at 200

I think I've come up with a useful scenario...maybe. :rolleyes: 50 shots at 200 yards, rimfire, whatever setup makes you happy. 22lr, 17 hmr, 22wmr, 17hm2, 17wsm, all brands, all types. Full benchrest setup, bipod, bags, or one-piece test rest, it doesn't matter. Grab a chunk of cardboard...

www.rimfirecentral.com

50 shot groups of every label of rimfire I could purchase.
Compare the results of Eley products.
They are all there. Which groups are smallest?
The cheap brands? The expensive brands?

The first post also includes a link to 25 shot results
in a tunnel at 100 yards, using multiple rifles.
Compare those group sizes for results vs price.
Eley Target and Club are not top quality ammo.

 

Sorry for the confusion, I was switching the action only, the barrel and stock were constants. All velocities listed were for the 24 inch barrel. The reason for the two actions is my original action is left handed and I was going to move it back to its original stock to use in factory with the 20 inch barrel if the opportunity ever arose.(an excuse to buy a new rifle) Since Right hand actions have so many more options for upgrading chassis was my reasoning for buying it. I had already chrono'd the rounds with it but not shot groups when the right hand rifle was delivered. So I don't know how it grouped either. I guess I can swap it back to test if needed.

I realize Eley Target and Club are the bottom rung. Just started there to work my way up till I find what works without breaking the bank for daily practice.

 

Well I went back out today for some more testing, I gave the barrel a good cleaning yesterday, made sure the chamber was clean, no carbon ring, and barre was clean.
It is still not grouping as consistent as I would like. Still under 1 MOA but I do see more uniformity coming together as I slowly change the torque settings Started with the cheaper Norma to make sure it would group.

Average Velocity of 1105
SD of 9
ES 48

@20.0 in/lbs .406" average
@22.5 in/lbs .382" average
@25.0 in/lbs .352" average
@27.0 in/lbs started having cocking issues will have to increase trigger travel

So hopefully I can improve on these when using better ammo. I plan on ordering some new flavors next month.

 

I like norma Tac for everyday plinking but I never get those kind of group averages at 50 yards. For every really great group there are a couple with nasty fliers that destroy the kind of avg your posting. That’s remarkable.

 

It is the flyers that are making it hard to nail this down. For these averages I shot 5, 5 shot groups each, then measured the top 4 of each group. The 5th was one that I knew I pulled at least one or more shot or knew I had a bad or worse than normal flyer that was contributed to ammo or me and not the rifle.
When I go back I will try the Club which should be bout the same velocity and hopefully better ES. As the groups tightened much of the spreads were vertical from velocity.

 

So you aren’t posting your actual avg group sizes with Tac 22. Understood.

 

I am trying to learn the rifles capability not mine or my mistakes.

• One group I know I pulled a shot or two (I was getting hot and tired) when I pulled the trigger, and the group was bad because of it.
• One group I had canted the rifle off of vertical which would skew the results
• One group was discarded due to a hole being torn in the target when I removed it from the cardboard. I guess some of the paper got stuck in the cardboard and ripped it when I pulled it off making it immeasurable. (which was a shame because it was a very tight group one of the tightest, which is why it made the tear)

So, no. One from each group of 5 was discounted. 4 of 5 were measured and then averaged.

 

As someone here once posted, My best groups are all one shot.

 

A rifle will only shoot as good as the one shooting it. Your bench technique has to be consistent before you can ever expect to fully see the rifle's potential. At this point you would do better to clamp it in a machine type rest removing any operator error. Just my opinion.

 

A rifle will only shoot as good as the one shooting it. Your bench technique has to be consistent before you can ever expect to fully see the rifle's potential.

(True, as I said, that is why I pulled the group where I knew the inconsistency was due to my errors)

At this point you would do better to clamp it in a machine type rest removing any operator error. Just my opinion.

Also true, But I would need some Generous soul (insert your name here) to either donate heavily or set up a Go Fund Me (insert your name here) account in my name to make that happen.

 

Soooooooo... Shoot what you got, don't expect perfection and just get some experience. Don't be hard on yourself. You have LOTS to learn. I shoot with a guy that has won and set Hunter High power benchrest records. He is tough and doesn't miss many condition changes. He will be the first to tell you we are at the mercy of the ammunition in the rimfire game.

 

Sooooo... What I am hearing is I shouldn't be holding my breath watching out for the UPS truck for a package from the Dutchman????

 

try shooting 30 shot groups and quit evaluating non statistically relevant "groups." Three and five shot groups might be fun to take pictures of, but don't represent the full spectrum of dispersion (hence your "fliers", which probably aren't). Lots of posts up above, maybe someone mentioned it, but the reason you get more velocity out of a longer barrel is because the bullet was still accelerating when it came out of the 20-inch, so the 24-inch shows that. Could be powder still burning (probably not, seems most .22s burn out about 18 inches) or it's actually just the internal pressure is still accelerating the bullet, that stops earlier with the shorter barrel.

 

Lots of posts up above, maybe someone mentioned it, but the reason you get more velocity out of a longer barrel is because the bullet was still accelerating when it came out of the 20-inch, so the 24-inch shows that. Could be powder still burning (probably not, seems most .22s burn out about 18 inches) or it's actually just the internal pressure is still accelerating the bullet, that stops earlier with the shorter barrel.

Yes I understand all that . I think I included too much initial information as to why I was switching things around that has confused people. So lets FORGET ABOUT THE 20 INCH BARREL.

The severe dispersion I was having I think I am working out. It was a combination of new unadjusted trigger, heavy trigger spring, and wrong action torque settings. I have replaced trigger springs and cleaned the trigger and getting closer to finding the correct torque for the action, and scrubbed the barrel.

Lets concentrate on discussing the 24 INCH BARREL and the SHIFT IN VELOCITY WHEN I CHANGE OUT THE ACTION.

• The velocity for the Eley Target Average is 1130 for the Right Hand Action and 1090 for the Left Hand Action
• The velocity for the Eley Club Average is 1098 for the Right Hand Action and 1085 for the Left Hand Action.

That is 40 fps difference for the Target ammo, and 13 fps for the Club ammo, Same Barrel, Different Action.
I had measured and shimmed the left hand action, and when the right hand action came in it measured the same as the shimmed left hand so I left it alone. Although it felt tighter.
I believe my measurements were wrong on it. I bought an adaptor for my caliper and will remeasure both today.

• Can head spacing difference make that much difference in velocity?
• How much does Head Spacing effect Accuracy?

 

You just got to put in the time. The more you shoot the more you learn. The more you learn, the better you will be at reading conditions and perfecting your technique. Only then can you really see the potential of your ammo and equipment and know if it was you that flubbed the shot or something wrong with the ammo or equipment. Enjoy to experience. Your not shooting for money. I hope

 

At first glance I thought you said I was put in time out. Definitely no $$$

 

A couple things are worth clarifying.

Safe head spacing has no effect on MV or on accuracy. Well-known rimfire gunsmith Bill Calfee noted this in his book and other reports.

Ammo MV is not consistent with barrel length. More important for ammo average MV is bore condition and characteristics, including bore diameter and its variation, bore concentricity (roundness), and bore smoothness/roughness.

To illustrate, two barrels from the same manufacturer that are the same length (diameter too, if anyone thinks that matters) can yield different average MVs for the same lots of ammo.

 

A couple things are worth clarifying.

Safe head spacing has no effect on MV or on accuracy. Well-known rimfire gunsmith Bill Calfee noted this in his book and other reports.

Ammo MV is not consistent with barrel length. More important for ammo average MV is bore condition and characteristics, including bore diameter and its variation, bore concentricity (roundness), and bore smoothness/roughness.

To illustrate, two barrels from the same manufacturer that are the same length (diameter too, if anyone thinks that matters) can yield different average MVs for the same lots of ammo.

Question?
So if head spacing has no effect on MV or accuracy, why do we measure it so closely and make shims to get it exactly right?

"Ammo MV is not consistent with barrel length. More important for ammo average MV is bore condition and characteristics, including bore diameter and its variation, bore concentricity (roundness), and bore smoothness/roughness."
Question?
In this incident we are talking about a single barrel with the same lots of ammo for both ammo's tested. (actually three, I saw the same increase 10-12 fps with Norma Tac 22 Right Hand Action over the Left Hand Action)

• So if it isn't the Head Spacing difference between the two actions, what explains the consistent increase in velocity?

 

For the lack of any other factors, firing pin strike difference. I've read that weak strikes can vause poor ignition and therefore erratic speeds.

 

Head space is important for function, not accuracy.

Calfee tested head space vs accuracy.
Started with tightest fit headspace and shot to establish accuracy.
Then shimmed the tenon to increase headspace and tested again.
Shimmed more and repeated until rifle failed to fire.

Comparison of results on target showed no loss of accuracy
from minimal headspace to where gap became too large
to allow the firing pin to impact and ignite the primer.

Kinda indicates that as long as it goes bang, y'er good.


To set headspace, ya' need to know the variations
of rim thickness to expect from all the manufacturer's.
Then set headspace a thousandth more than the largest.
That way Eley, RWS, Lapua and CCI will all function.

 

Question?
So if head spacing has no effect on MV or accuracy, why do we measure it so closely and make shims to get it exactly right?

The headspace that CIP and SAAMI both have 0.043" as the standard specification. Rimfire manufacturers strive to ensure that this is the headspace on the firearms they make. Sometimes there are firearms that don't meet the specs, so shooters may wish to double check.

Having said that, some shooters seek different headspace in an wasted effort to wring more accuracy out of their rifles. The most effective way to achieve better accuracy is to use better, more accurate, ammo. Shortcuts like reducing headspace by 0.001" or so inches is not a solution that works.

Question?
In this incident we are talking about a single barrel with the same lots of ammo for both ammo's tested. (actually three, I saw the same increase 10-12 fps with Norma Tac 22 Right Hand Action over the Left Hand Action)

• So if it isn't the Head Spacing difference between the two actions, what explains the consistent increase in velocity?

When using the same barrel the handedness of the action/receiver has no relationship to changes in ammo average MV.

What's changed is that different rounds are being evaluated for muzzle velocity. No two rounds can be used twice.

Different boxes of ammo from the same lot can have different average MVs. This is especially true of entry level match or target ammos. In addition, testing small numbers of rounds can easily produce MVs that differ because small sample sizes can produce unreliable data.

Furthermore, if testing was done at different times it's quite possible that the temperature was not the same each time. When it's warmer .22LR ammo will be faster. When it's cooler it will be slower.