Chipmunk 22 vs Marlin vs Slingshot vs Slap Shot vs RimX

[rlaunay]

Perhaps this needs further explanation. Centerfire accuracy is generally linear at the distances under discussion in this thread. This means that as distance doubles, group size generally doubles. To put it another way, if a CF rifle shoots 1 MOA at 100, it's not unreasonable to generally expect 1 MOA at twice the distance. The difference between centerfire and rimfire is that .22LR accuracy is non-linear. That means that as distance doubles, group sizes more than double.

I had started writing a lengthy response to this, but I'll just leave a few observations and then retire and admonish myself for making the mistake of thinking this was a thread started looking for healthy discussion about possible answers instead of the usual call for validation of pre-held beliefs.

Readers should note:

• Once a bullet leaves the case, it has no memory of what gave it the push to accelerate.
• Attempting to equate centerfire bullets being linear in their prime ranges with rimfire bullets being non-linear in distances several times beyond the distances they were designed to shoot at is misleading. (Rimfire accuracy is pretty darn linear from 12m to 25m to 50m, but pretty darn non-linear 100m to 200m to 300m. Centerfire accuracy is pretty linear from 100m to 300m to 600m, but not very linear 600m to 1200m to 2400m *adjust as necessary as bore size increases*)
• If we were talking about any other caliber, it would be a rare thing indeed to argue that a low BC, light for caliber bullet that may perform slightly better at 100m would continue to hold that advantage at 1000m over it's high BC, heavy for caliber competitors.. but, apparently this isn't the case for 22LR because...... rimfire? - see first note. *Also note: This is not advocating for any specific design - rather just an observation that "if" we can produce a system that provides a stable, higher BC bullet travelling at similar velocities, it would answer the second part of the original question.*
• We don't shoot in vacuums. Accuracy is affected by environmental forces. Designs that reduce the effects of those forces are more likely to produce more accurate results. As long as the minimizing of those forces is greater than any loss of close range accuracy from less consistent ammunition, it is possible to produce a net positive result. That is what we're all waiting to see - can any changes to bullets or barrels make enough different to be worthwhile.

Posting in the rimfire forum is like eating KFC. Once a year, it seems like a great idea. 3 hours later, you'll regret that decision. See you next year!

 

[Canuck44]

I had started writing a lengthy response to this, but I'll just leave a few observations and then retire and admonish myself for making the mistake of thinking this was a thread started looking for healthy discussion about possible answers instead of the usual call for validation of pre-held beliefs.

Readers should note:

• Once a bullet leaves the case, it has no memory of what gave it the push to accelerate.
• Attempting to equate centerfire bullets being linear in their prime ranges with rimfire bullets being non-linear in distances several times beyond the distances they were designed to shoot at is misleading. (Rimfire accuracy is pretty darn linear from 12m to 25m to 50m, but pretty darn non-linear 100m to 200m to 300m. Centerfire accuracy is pretty linear from 100m to 300m to 600m, but not very linear 600m to 1200m to 2400m *adjust as necessary as bore size increases*)
• If we were talking about any other caliber, it would be a rare thing indeed to argue that a low BC, light for caliber bullet that may perform slightly better at 100m would continue to hold that advantage at 1000m over it's high BC, heavy for caliber competitors.. but, apparently this isn't the case for 22LR because...... rimfire? - see first note. *Also note: This is not advocating for any specific design - rather just an observation that "if" we can produce a system that provides a stable, higher BC bullet travelling at similar velocities, it would answer the second part of the original question.*
• We don't shoot in vacuums. Accuracy is affected by environmental forces. Designs that reduce the effects of those forces are more likely to produce more accurate results. As long as the minimizing of those forces is greater than any loss of close range accuracy from less consistent ammunition, it is possible to produce a net positive result. That is what we're all waiting to see - can any changes to bullets or barrels make enough different to be worthwhile.

Posting in the rimfire forum is like eating KFC. Once a year, it seems like a great idea. 3 hours later, you'll regret that decision. See you next year!

A wise man says little and reads a lot. Thank-you for this post.

Take Care

Bob

 

[grauhanen]

I had started writing a lengthy response to this, but I'll just leave a few observations and then retire and admonish myself for making the mistake of thinking this was a thread started looking for healthy discussion about possible answers instead of the usual call for validation of pre-held beliefs.

Readers should note:

• Once a bullet leaves the case, it has no memory of what gave it the push to accelerate.
• Attempting to equate centerfire bullets being linear in their prime ranges with rimfire bullets being non-linear in distances several times beyond the distances they were designed to shoot at is misleading. (Rimfire accuracy is pretty darn linear from 12m to 25m to 50m, but pretty darn non-linear 100m to 200m to 300m. Centerfire accuracy is pretty linear from 100m to 300m to 600m, but not very linear 600m to 1200m to 2400m *adjust as necessary as bore size increases*)
• If we were talking about any other caliber, it would be a rare thing indeed to argue that a low BC, light for caliber bullet that may perform slightly better at 100m would continue to hold that advantage at 1000m over it's high BC, heavy for caliber competitors.. but, apparently this isn't the case for 22LR because...... rimfire? - see first note. *Also note: This is not advocating for any specific design - rather just an observation that "if" we can produce a system that provides a stable, higher BC bullet travelling at similar velocities, it would answer the second part of the original question.*
• We don't shoot in vacuums. Accuracy is affected by environmental forces. Designs that reduce the effects of those forces are more likely to produce more accurate results. As long as the minimizing of those forces is greater than any loss of close range accuracy from less consistent ammunition, it is possible to produce a net positive result. That is what we're all waiting to see - can any changes to bullets or barrels make enough different to be worthwhile.

Posting in the rimfire forum is like eating KFC. Once a year, it seems like a great idea. 3 hours later, you'll regret that decision. See you next year!

I hope you're not choking on the bones. According to the Hip,

They'd say, "Baby, eat this chicken slow
It's full of all them little bones
Baby, eat this chicken slow
It's full of all them little bones"

Your posts here have served to be a distraction. Here's why.

You never mentioned the best .22lr of all, the Cooey Ace.

Let me be more clear.

Rifle A is a 22LR rifle that shoots 0.1MOA groups at 50m every single time using the best benchrest ammos available.

Rifle B is a centerfire rifle that shoots 1.0 MOA groups at 50m every single time using the highest BC heaviest for caliber bullets available.

To make it more clear - let's spread our distances apart even more and ask a simple question.

Given the two rifles, which rifle would be predicted to produce the smaller group at 600m?

If you can with a straight face suggest the 22lr has a chance, this isn't a conversation being had in good faith and not worth continuing.

That's a very logical question. Who would agree or disagree?

 

[Maple57]

Here's a video on arrow tuning that might illustrate one of the less obvious aspects of something in flight.

Now bullets do not have feathers, and they don't bend like an arrow in flight, but an arrow that does not leave the bow pointing straight will porpoise back and forth until it stabilizes. All that porpoising causes the arrow to hit low because its slightly side ways, which essentially lowers the BC.

We calculate and accept BC as a factor of both weight and bullet diameter on the assumption that the bullet is always pointing directly along the axis of flight, but what if this assumption is not realistic, or is only realistic under the most ideal conditions?

An arrow starts off kicking away and eventually settles down. Some shooters believe bullets do something similar and eventually go to sleep... I don't want to argue if this is true or not, but what if we look at it in reverse?

What if the aerodynamic effects and possibly even variations in wind pressure over the flight of the bullet affect the POI differently as a result of spin rate?

We know that it does as spin rate affects aerodynamic jump, but can variations in wind affect the stability of the flight path via a tilting of the bullet in a slightly sideways attitude so as to decrease the sectional density. (Essentially key holing just a little bit.) This would cause the affected bullets to hit low.

So at long range, (all things being equal) are bullets that hit high the result of a perfectly flying bullet and bullets that hit low the result of an imperfectly flying bullet?

Can such results be associated with barrel twist rate?

I find it difficult to accept that it is not, at least to some degree.

We also know that spin rate per forward inch increases downrange. The spin rate in RPMs remains almost constant while a bullet is in flight. So once a bullets slows down to half the muzzle velocity, the spin rate per forward inch will be twice what it was leaving the barrel. So how does this ever increasing spin rate per forward inch affect the attitude of the projectile and thereby accuracy at distance?

 

[Alpheus]

We know that it does as spin rate affects aerodynamic jump, but can variations in wind affect the stability of the flight path via a tilting of the bullet in a slightly sideways attitude so as to decrease the sectional density. (Essentially key holing just a little bit.) This would cause the affected bullets to hit low.

So at long range, (all things being equal) are bullets that hit high the result of a perfectly flying bullet and bullets that hit low the result of an imperfectly flying bullet?

Can such results be associated with barrel twist rate?

I think the answer is essentially, yes. How much a bullet angles into the wind depends on it's BC; a higher BC bullet angles less and therefore experiences less wind deflection.
A marginally stable bullet has it's BC depressed, and will therefore experience more wind deflection then an identical fully stabilized bullet.

Playing with my Kestrel, for my .223 at 1046yds with a 20mph crosswind, I get 6.56mils of windage with a 1-7 twist. 1-9 is 6.64mils, 1-11 is 6.68mils, 1-13 is 6.72mils

We also know that spin rate per forward inch increases downrange. The spin rate in RPMs remains almost constant while a bullet is in flight. So once a bullets slows down to half the muzzle velocity, the spin rate per forward inch will be twice what it was leaving the barrel. So how does this ever increasing spin rate per forward inch affect the attitude of the projectile and thereby accuracy at distance?

Correct, if the bullet is stable leaving the muzzle, it's stability increases as it goes downrange. This is why if a bullet is going to start tumbling, it will do so in the first 25-50yards of flight.

Tying this in with your earlier point, what if you firing a bullet with a SG of say 1.4, this means the BC is being reduced by about 3%. If the SG rises to 1.5 further down range and it's BC is optimized, does this mean it will experience more wind deflection at shorter ranges? BC is also a product of the velocity, lower speed means lower BC. Even if the BC increases due to improved stability, will this be cancelled out do to the dropping velocity?

 

[Maple57]

Tying this in with your earlier point, what if you firing a bullet with a SG of say 1.4, this means the BC is being reduced by about 3%. If the SG rises to 1.5 further down range and it's BC is optimized, does this mean it will experience more wind deflection at shorter ranges? BC is also a product of the velocity, lower speed means lower BC. Even if the BC increases due to improved stability, will this be cancelled out do to the dropping velocity?

This effect is what I think people mean by going to sleep... Regardless of what Brian Lytz says.

I don't think the low velocity cancels out the BC exactly. I think a bullet has an optimal BC per velocity, meaning center line directly along the axis of travel is ideal. If a bullet adopts an attitude that is off axis, the BC would decrease from that optimal BC in accordance with the corresponding drop in aerodynamic efficiency caused by the off axis attitude.

There was a video posted on YouTube recently by a couple CRPS guys out on a frozen lake in Quebec who (if I remember correctly) noted sideways impacts on the target at long range. That has to mean something toward the point of this thread.

Found it... 1000 Yards with 22 LR

I know F Class shooters who frequently find that at long range, a little faster spin rate tends to work better with a given bullet than just enough. If you want to make a mistake on spin rate for center fire, go a bit quicker is the prevailing advice. But does this advice apply to sub sonic rounds like a 22LR?

 

[Alpheus]

There was a video posted on YouTube recently by a couple CRPS guys out on a frozen lake in Quebec who (if I remember correctly) noted sideways impacts on the target at long range. That has to mean something toward the point of this thread.

If you check out their first video, you will see some of the flattened bullets. They aren't hitting sideways, but nose on at an angle.

The question is if that angled impact is because the bullet is falling normally (A) and simply due to the high descending angle and the tilted target, or if the bullet is traveling with excessive yaw (B) from under-stabilization. Another example of this is oblong bullet holes in paper at long range.

Another possibility is the bullet is "failing to trace", and flying with a pronounced nose up angle as it descend, but I doubt this since this problem is normally only seen is early high angle artillery (eg 18th and 19th century), and not small arms.

I know those guys on the lake, I shoot with them in Ottawa, I'll ask if they still have the bullets lying around. If they were flying normally, then the angle of the impact to the bore of the bullet should be equal for every impact. If they were yawing excessively, then the angle should vary as some would hit yawing above, below, left or right of the line of flight.

I know F Class shooters who frequently find that at long range, a little faster spin rate tends to work better with a given bullet than just enough. If you want to make a mistake on spin rate for center fire, go a bit quicker is the prevailing advice. But does this advice apply to sub sonic rounds like a 22LR?

I've been reviewing part 1 of Modern advancements on LR shooting, the first 5 chapters are all about stability. Problem is all the tests and experiments are with supersonic centerfire bullets...

 

[Alpheus]

Got a picture of them:

Photo isn't ideal, but looks pretty consistent to me.

 

[grauhanen]

This is a welcome diversion from the debate over which is a better 3000 yard shooter, the stock 10/22 or a slingshot or a slap shot.

As one of the participants who made the youtube recording explained, what their video shows is that "a 1000 yard 22 shot is possible." They recorded seven hits out of 250 shots, a one in 37 success rate. With enough shots and a tolerance for a high rate of failure, there's no reason why .22LR hits at even further distances isn't possible.

The bullets shot at their distant target were not striking sideways. Curiously, it seems what surprised them, initially at least to go by their running commentary, was that the bullets struck at an angle (see pictures below). They seemed to have figured out why this happened by the time their video was concluding. (Edit to add that while I was preparing this post Alpheus showed the bullet pictures and gave the explanation.)



Nearby to where the shooting was done in the video there were some ice fishermen. As a final epitaph to the southbound nature this thread has unfortunately taken, perhaps its possible to end with the observation that the creators of the video thought it was worthwhile to acknowledge their phallic "artwork" at the end of their recording.

 

[RabidM4U5]

LOL yeah grauhanen, this thread is full of a bunch of... well, see above photo

 

[Ganderite]

If you check out their first video, you will see some of the flattened bullets. They aren't hitting sideways, but nose on at an angle.

The question is if that angled impact is because the bullet is falling normally (A) and simply due to the high descending angle and the tilted target, or if the bullet is traveling with excessive yaw (B) from under-stabilization. Another example of this is oblong bullet holes in paper at long range.

Another possibility is the bullet is "failing to trace", and flying with a pronounced nose up angle as it descend, but I doubt this since this problem is normally only seen is early high angle artillery (eg 18th and 19th century), and not small arms.

I know those guys on the lake, I shoot with them in Ottawa, I'll ask if they still have the bullets lying around. If they were flying normally, then the angle of the impact to the bore of the bullet should be equal for every impact. If they were yawing excessively, then the angle should vary as some would hit yawing above, below, left or right of the line of flight.

...

Look at the arc the bullet takes at the end, as it tips over and goes down.

Remember that the bullet is spinning very fast. It is a gyro, with gyroscopic stability.

If you have ever played with a spinning gyro, you know that if you tip it in one direction, it rotates 90 degrees.

If a bullet tips over like the diagram shows, it will tip sideways.

Those of us who have marked targets shot at long range have seen the bullets hitting the target sideways.

 

[Tokay444]

Very few bullets will achieve “balanced flight” and impact the target with a nose down attitude as the illustration implies. Those bullets impacted the target with a nose up attitude, on the downward segment of their flight path.

 

[Daver_II]

Do not most bullets travel nose up during their flight path by design?

 

[Tokay444]

Do not most bullets travel nose up during their flight path by design?

If the barrel is pointing up when they’re fired, yes.

 

[Daver_II]

If the barrel is pointing up when they’re fired, yes.

No I mean similar to the flight of a football,

 

[Tokay444]

No.
Very few exhibit, “balanced flight”, but your posts seem contradictory to each other.

 

[grauhanen]

The laws of psychics say that this is only possible some of the time. At other times it's not.

 

[Daver_II]

Angle of attack,

projectile travels with an nose up orientation along its trajectory, relating to its longitudinal axis.

I believe this angle grows over distance as the spin stabilization of the projectile keeps the longitudinal axis parallel (or mostly so while stable) to the line of departure. Therefore as the bullet follows its trajectory, the flight path and and and longitudinal axis of the projectile diverge.

At least until the trans-sonic barrier.

 

[Tokay444]

How are you thinking a football flies?

 

[Daver_II]

How are you thinking a football flies?

same way?

The more accurate, and longest throws have stable spin and an nose up angle.



Granted I know that .22lr bullets and not the same as centerfire projectiles, but over long distance the Data I have seen reflects the same principles.