The effects of the transition from super to sub sonic on the 22lr

[justin amateur]

I've run a few web searches on the topic but most point to a study done on a SMK boat tail hollow point
published by the Aberdeen Ballistics Lab. Plenty of folks using that study to justify blaming the transition
for poor accuracy with the 22lr. Problem...the 22lr is not a long, slender, tail heavy, needle nose projectile.
It's a short, stubby, round nosed cylinder and as such is affected differently as the center of pressure
shifts forward during the transition. A boat tail SMK will pitch and yaw heavily, as the center of pressure moves to the nose
but according to the only study I can find regarding the transition and the 22lr, produces less than 2 degrees of yaw
which has "insignificant" effect on accuracy. (McCoy's publication on Match 22lr)

https://apps.dtic.mil/dtic/tr/fulltext/u2/a229713.pdf

Are there any other studies available or does it all go back to the SMK publication?

 

[justin amateur]

Bueller? Bueller? Bueller?

Is this microphone working?

Apparently the only study that actually relates to the 22lr was by McCoy.
All the rest have to do with center fire projectiles running at 2000 FPS plus.
Designed for optimum flight at supersonic velocities.
The 22lr was designed for use to provide stable flight at all velocities
based on 1800's experience with cast lead bullets. Compare the 22lr to the Minie ball.
Round nose, heel expands to seal the bore, black powder propellant. Very stable in flight.
That's why the 22lr is pretty much unaffected by the transition.

If you find any other studies relating to the 22lr that don't link back to center fire testing, post 'em.

So far, it looks like the true cause of poor accuracy with hi-v 22lr
is entirely due to low quality cartridges being tested, not transition.

 

[Just Chuck]

Interesting topic. It might be worth throwing some supersonic rounds out to 3-400 yards on paper to see if there is any sign of tumble/instability. Impact on paper ought to show what orientation the round is when it hit.

Just for fun, I loaded a CCI 32gr HP rated at 1640fps into Strelok and it shows subsonic at 100yards, so stability problems may show up at longer ranges. I dunno....just some random thoughts.

I'll watch your thread and see what else is posted. I'm sure Bryan Litz will be adding to this.

 

[acourvil]

I’m not aware of any studies for this. I know from experience that in pellet guns diablo style pellets lose stability in the transonic zone, but that some slugs (closer to .22LR shape bullets) seem to do better. And while not a direct correlation with accuracy, wind drift increases in the transonic zone. But it would be really interesting to see some real data.

I have been playing with Cutting Edge hand-loaded .22 solids, and while I have not generated any real data, I will say that anecdotally I am not seeing worse results for faster loads, and to date the better loads have been supersonic.

 

[Dr. Strangelove_207]

From my amateurish testing, RWS R50 has performed better in a 100yd tunnel range than RWS R100. Haven’t had the chance to properly test both at longer ranges in nil-wind conditions.

 

[justin amateur]

I've had R50 produce better results than R100 too Doc.
Also had R100 do better than R50...is that because of the rated mv?
Or is it due to typical lot variations? Get a good batch get good results.
Get a Monday morning lot or Friday afternoon brick, blame goes to cartridge quality,
not due to rated mv. Manufacturing defects are the more likely culprit than transition.

 

[blessyourheart]

I have nothing pertinent to add, except I really like this pic from Nasa. And that they used it as an example of a 13 "LIGHT" year long trail of a star.

A bullet traveling through air at about 1.5 times the speed of sound can be seen in this image. When a moving object breaks the sound barrier, a shock wave and often turbulence are created. In this image, the curved line at the nose of the bullet is a shock wave. Other shock waves can be seen alongside the bullet, and a turbulent wake trails behind it.
NASA's Galaxy Evolution Explorer captured an image of a racing star, called Mira, that resembles this bullet photo. The ultraviolet image shows a gigantic shock wave, called a bow shock, in front of the star, and an enormous, 13-light-year-long trail of turbulence in its wake. Nothing like this tail has ever been seen before.

 

[obx22]

I haven’t performed exhaustive testing at distance, just 300 yds on paper, 400 on steel, same ammo and primarily 2 rifles so far. Nice clean round holes in paper, and circular dime size disks of lead impacts lay in the grass under the steel. If there’s instability, I’m not sure how you would determine it.
As for the shadow graph above,
I’m just as puzzled by the smaller projectile high left of the slug. A sliver of lead of powder grain perhaps? Regardless it cuts a similar wake through the atmosphere.

 

[justin amateur]

Pitch and yaw cause keyholing, correct?
So transonic turbulence should cause visible evidence of such at extended range, right?

I must be missunderstanding something....

Plenty of spread due to poorly made cartridges, but no keyholing.
No doubt these cartridges are exceeding Mach 1.2, then dropping back down completely through the transition zone, right?

 

[JBoomhauer]

Pitch and yaw cause keyholing, correct?
So transonic turbulence should cause visible evidence of such at extended range, right?

I must be missunderstanding something....

Plenty of spread due to poorly made cartridges, but no keyholing.
No doubt these cartridges are exceeding Mach 1.2, then dropping back down completely through the transition zone, right?

They are not necessarily going to become completely unstable.

 

[justin amateur]

Nope, they aren't JB. McCoy noted the transition causes less than a 2 degree yaw, which has "insignificant" effect on accuracy.
I have hundreds of target results and haven't seen anything that indicates problems caused by supersonic turbulence.
Plenty of strays due to gusts, operator error and beat up cartridges...but not transition caused.

Could it be the transition is a handy excuse for poor skills or crappy cartridges?
Need to have something to blame the sloppy results on, eh?

 

[JBoomhauer]

Like many things. It is very real but the magnitude is often overblown.

Lots of “Voodoo magic” people like to look at instead of focusing on the low hanging fruit.

 

[BLJ]

Tag for reference.

 

[Milo 2.5]

Pitch and yaw cause keyholing, correct?
So transonic turbulence should cause visible evidence of such at extended range, right?

I must be missunderstanding something....

Plenty of spread due to poorly made cartridges, but no keyholing.
No doubt these cartridges are exceeding Mach 1.2, then dropping back down completely through the transition zone, right?

I don't think cardboard would be the best backer for this, with a 24 pack box, thin cardboard tight against even wood may yield trailing edges if not stable. Have you ever shot groups into cloroplast? All bullets close to the first hole go in the first hole.
Lot of guys swear by higher velocity ammo for distance, grant it that it is not copper jacket bullets. I tried, SK Long Range and High Velocity, just wrote it off as my rifles did not like higher speed ammo, transition never entered my mind. At 200 it wasn't bad, by 300 it sucked.
Here is a 600 yard target, 2nd attempt that far, first one was a disaster, so I bought bigger steel. Great night to shoot 600, very little wind, fishtailing behind me. My hit ratio was 60%, 5 - 10 rd mags, 18" plate. I put 5 on a 24" plate to start, as my first outing I realized that 90% of our misses were high, just couldn't pick it up.
Enlarge the pic, my question is, are the impacts w/o a full starburst around them unstable, or deformation of the bullets? LOL, I utilized every inch of the 18 inches.

 

[justin amateur]

It's not about the rifle having an affinity for the brand name Milo, from what I've seen
using both the chronograph and multiple barrels, it's all about cartridge quality.
Well made cartridges with tight mv's produce great results from all of my rifles.
Cartridges with mv spread and bullet asymmetry show trajectory dispersion and strays.
Lot variations are to blame for the changes in results.

I have used cardboard to document keyholing.
Shows up very well at all the distances I've tried.
No doubt when a 22lr comes in with a pronounced yaw at impact.
That elongated hole is very recognizable. Give me a minute to dig in my archive....

Aguila showing some serious wobbles....

 

[JBoomhauer]

Using the eley force load above….

Transonic will be from Mach 1.2 to .8.

1215 is starting out already well in that transonic zone and will be outside of that zone at around 170y.

Those effects may not be visible on the target at 300 anyway, other than possibly a larger group.

 

[justin amateur]

JB, look at the Eley Contact pic and the Eley Force pic.
Same 42 grain bullet off the same assembly line.
Ones sub-sonic, the other super-sonic, same rifle and conditions, shot minutes apart,
and the group sizes are almost the same...where's that transition supposedly causing poor results?

 

[JBoomhauer]

Lol it’s a transonic range, not a transonic wall.

They are both in it, one just longer than the other.

 

[Milo 2.5]

It's not about the rifle having an affinity for the brand name Milo, from what I've seen
using both the chronograph and multiple barrels, it's all about cartridge quality.
Well made cartridges with tight mv's produce great results from all of my rifles.
Cartridges with mv spread and bullet asymmetry show trajectory dispersion and strays.
Lot variations are to blame for the changes in results.

I have used cardboard to document keyholing.
Shows up very well at all the distances I've tried.
No doubt when a 22lr comes in with a pronounced yaw at impact.
That elongated hole is very recognizable. Give me a minute to dig in my archive....

Aguila showing some serious wobbles....

My post was in conjunction with wind deflection post, HV vs target velocity. I think we are trying to over complicate this shit. Reading J Bell's posts concerning longer barrels, where ammo has to be in a drag scenario, and the results, which are fantastic, I see no reason unless hunting, to shoot HV ammo.
I think my 20" Rim X barrel may still be in gain mode, but I need to chrono my 22" Vudoo, I have a feeling ammo is on the downswing, I just haven't yet. Actually I am waiting on a 40 moa base for it to compare 400+ ranges, at 400, they shoot close to identical. Do it all in one trip.

 

[justin amateur]

Understood, Milo.

JB, y'er right...it's the interval where the velocity is decreasing.
The pressure front/shockwave is shifting forward toward the nose.
The change in pressure doesn't cause much of anything with regards to the trajectory path,
based on documented results. MV spread and factory defects are the real irritants.

 

[JBoomhauer]

With your force and contact groups above there is about a 35y difference in transonic between each other.

With that being said, I would not expect a huge difference in group size.

I agree other factors are much more important.

 

[obx22]

It's not about the rifle having an affinity for the brand name Milo, from what I've seen
using both the chronograph and multiple barrels, it's all about cartridge quality.
Well made cartridges with tight mv's produce great results from all of my rifles.
Cartridges with mv spread and bullet asymmetry show trajectory dispersion and strays.
Lot variations are to blame for the changes in results.

I have used cardboard to document keyholing.
Shows up very well at all the distances I've tried.
No doubt when a 22lr comes in with a pronounced yaw at impact.
That elongated hole is very recognizable. Give me a minute to dig in my archive....

Aguila showing some serious wobbles....

What twist? Never had anything close to that round out of that ammo. At 50m I was getting silhouette keyholes out of every rifle I tested in.

 

[justin amateur]

Obx, those results are at 200 yards with the Aquila Sniper SubSonic 60 grain 22lr.
Sent with a CZ 455 Varmint with a Lilja 21 inch barrel, 1:16 twist.
Some of those bullets were impacting at almost 90 degrees to direction of travel.

 

[obx22]

Obx, those results are at 200 yards with the Aquila Sniper SubSonic 60 grain 22lr.
Sent with a CZ 455 Varmint with a Lilja 21 inch barrel, 1:16 twist.
Some of those bullets were impacting at almost 90 degrees to direction of travel.

Only “use” I’ve found for that ammo is slugging bores

 

[Bf7]

Tag

 

[MarshallDodge]

It's not about the rifle having an affinity for the brand name Milo, from what I've seen
using both the chronograph and multiple barrels, it's all about cartridge quality.
Well made cartridges with tight mv's produce great results from all of my rifles.
Cartridges with mv spread and bullet asymmetry show trajectory dispersion and strays.
Lot variations are to blame for the changes in results.

I have used cardboard to document keyholing.
Shows up very well at all the distances I've tried.
No doubt when a 22lr comes in with a pronounced yaw at impact.
That elongated hole is very recognizable. Give me a minute to dig in my archive....

Aguila showing some serious wobbles....

Isn't the Sniper loaded with a really long bullet? I would think a faster twist would help it.

 

[Bf7]

 

[acudaowner]

looks a little like this but in the air

 

[SanPatHogger]

My buddy had a couple boxes of 60gr subsonics. Out of his pistol and his Ruger American rimfire is sucked. I suggested shooting it in his AR conversion with a 1:7 twist barrel. Guess what... It shot pretty sweet. Bullet weight, velocity, barrel twist.... All need to mesh

 

[bulletbluesky]

Interesting thread.
I'm not at all expert on .22LR, but I would put blame on supersonic flow regime effect on such round nose projectiles. Noticed long ago for handgun/submachine 7.62x25 mm FMJ bullets. These bullets were not more accurate in tests when fired at 1600 ft/s than at 1000 ft/s at 50 meter range no matter what kind of spin rate they were put on

 

[Inline6]

I don't think cardboard would be the best backer for this, with a 24 pack box, thin cardboard tight against even wood may yield trailing edges if not stable. Have you ever shot groups into cloroplast? All bullets close to the first hole go in the first hole.
Lot of guys swear by higher velocity ammo for distance, grant it that it is not copper jacket bullets. I tried, SK Long Range and High Velocity, just wrote it off as my rifles did not like higher speed ammo, transition never entered my mind. At 200 it wasn't bad, by 300 it sucked.
Here is a 600 yard target, 2nd attempt that far, first one was a disaster, so I bought bigger steel. Great night to shoot 600, very little wind, fishtailing behind me. My hit ratio was 60%, 5 - 10 rd mags, 18" plate. I put 5 on a 24" plate to start, as my first outing I realized that 90% of our misses were high, just couldn't pick it up.
Enlarge the pic, my question is, are the impacts w/o a full starburst around them unstable, or deformation of the bullets? LOL, I utilized every inch of the 18 inches.

I know it is an older post. It is bullet deformation.

Here is one of my bullets recovered at 700 yards

I'm shooting LSLR it is running at 1125ish depending on temps. Have been very happy with the results thus far.

 

[jgraves]

I had an interesting experience with Lapua Biathlon Xtreme (or possibly Polar Biathlon, was lot testing both) a few months ago. I'll have to dig up the data some other evening, but I shot 90 10 shot groups at 100 yards over 2 days, recording mv for almost all shots (user error setting up Magnetospeed) and environmentals every few groups. The rifle is a V-22 with 18" MTU profile barrel and Magnetospeed is chassis mounted.

After shooting several ~MOA groups, I noticed the first shot from a mag drop ~1.5" low with the remaining 9 shots near the previous POI. After repeating this a couple times, I held the first round in the chamber for a minute or 2 before firing which yielded ~MOA group at initial POI. This sort of worked for a couple more groups before holding the round in the chamber would not prevent the low shot. This was soon followed by random "fliers" in the groups. I also observed "good" shots were below ~1130fps and "bad" (typically low) shots around ~1135fps. This trend spanned at least 2 lots of same ammo.

My thoughts on the first round being fast is due to the ammo in the box warming up earlier than the barrel in the shade. POI shift could then be accounted for by mv being almost exactly Mach 1, or barrel harmonics. Velocity variation alone does not account for vertical shift.

Another (unlikely) thought is a carbon / wax ring developing and hardening as the chamber cools while I make notes and load a mag for the next group. The harder obstruction causing slightly higher initial pressure before the bullet leaves the chamber and swaging the bullet to a slightly smaller diameter, resulting in higher average pressure and less fraction (higher velocity) and looser fit (less accuracy).

FWIW, I bought a case of Biathlon Xtreme, despite the fliers, and will reserve it for days I take hot chocolate and hand warmers to the range.

 

[justin amateur]

JG, next time you get a chance, fire 10 shots,
remove the bolt, then look down the bore.
Let me know just how many burn residue clumps you see.
Note the clump sizes and their locations.
They are caused by water vapor condensing on burn particulates
and clumping together during the pressure drop
as each bullet leaves the barrel. Think what happens
if those clumps dry and harden,
if there's too long an interval between shots.
How will that affect a bullet?

 

[grauhanen]

After shooting several ~MOA groups, I noticed the first shot from a mag drop ~1.5" low with the remaining 9 shots near the previous POI. After repeating this a couple times, I held the first round in the chamber for a minute or 2 before firing which yielded ~MOA group at initial POI. This sort of worked for a couple more groups before holding the round in the chamber would not prevent the low shot. This was soon followed by random "fliers" in the groups. I also observed "good" shots were below ~1130fps and "bad" (typically low) shots around ~1135fps. This trend spanned at least 2 lots of same ammo.

This experience may not be unusual. There are ammo-related reasons for this, and different lots will be better or worse than others.

What may have been unusual is if all the rounds continued to produce MOA groups at 100. Often this level of consistency -- regular MOA -- isn't seen throughout a random lot. Wind aside, at 100 many lots will have what look like fliers because .22LR rounds simply don't always go where they are aimed.

 

[jgraves]

Justin, I think you talked me out of any sort of barrel fouling theory, including my carbon / wax ring theory, as they don't account for chamber hold time and velocity threshold correlation to accuracy. To be fair, I haven't shared any data yet.

grauhanen, I want to share the data before commenting too much. The data set is large enough and behaviour occurred enough times that random variation is unlikely.

 

[jgraves]

Below is data from 3 lots of Lapua Biathlon Xtreme, 10x 10 shots groups, at approximately 104 yards. All groups shot on the same day, from mid-morning to mid-afternoon, on Labour Day Monday, in the order shown. Barrel had likely last seen 320ish rounds of Lapua Polar Biathlon the previous day although may have been cleaned the previous evening. Groups were measured using Gordon's Reloading Tool.

I also have target images and notes during the day that I'll post once I organize them.

Group ES is what we typically think of as group size, IIRC in MOA. Group SD and Group Mean refer to shot distribution on target while Min, Max, Avg, S-D and ES refer to velocity, within that shot string / target (typically 10 shots). Δ Max is the change in max velocity by omitting the first shot of that string. Across 30 groups, the first shot was never the slowest.

Ammo

Lot

Brake

Shots:

Group ES

Group SD

Group Mean

Min

Max

Avg

S-D

ES

Δ Max

Biathlon Xtreme

357X55/504502

Yes

10​

1.543​

0.329​

0.842​

1081​

1127​

1095.6​

13.3766​

46​

18​

Biathlon Xtreme

357X54/500354

Yes

10​

1.367​

0.274​

0.704​

1089​

1110​

1098.4​

6.113737​

21​

0​

Biathlon Xtreme

357X55/504391

Yes

10​

1.236​

0.246​

0.665​

1082​

1101​

1089​

6.110101​

19​

6​

Biathlon Xtreme

357X55/504502

Yes

10​

0.785​

0.137​

0.426​

1091​

1114​

1098​

7.498148​

23​

5​

Biathlon Xtreme

357X54/500354

Yes

10​

0.884​

0.142​

0.463​

1094​

1118​

1108.4​

6.785606​

24​

0​

Biathlon Xtreme

357X55/504391

Yes

10​

1.512​

0.347​

0.813​

1085​

1111​

1097​

7.086764​

26​

8​

Biathlon Xtreme

357X55/504502

Yes

10​

1.122​

0.16​

0.596​

1084​

1102​

1096.5​

5.562773​

18​

0​

Biathlon Xtreme

357X54/500354

Yes

10​

0.983​

0.15​

0.588​

1096​

1118​

1105.9​

7.964505​

22​

2​

Biathlon Xtreme

357X55/504391

Yes

10​

1.127​

0.269​

0.593​

1095​

1109​

1101.4​

4.168666​

14​

4​

Biathlon Xtreme

357X55/504391

Yes

10​

2.011​

0.496​

1.052​

1094​

1115​

1101.3​

6.896859​

21​

0​

Biathlon Xtreme

357X55/504391

Yes

10​

1.264​

0.26​

0.691​

1093​

1115​

1105.8​

5.652925​

22​

0​

Biathlon Xtreme

357X55/504502

Yes

10​

0.969​

0.137​

0.507​

1097​

1118​

1107.4​

6.883152​

21​

0​

Biathlon Xtreme

357X55/504502

Yes

10​

2.083​

0.324​

1.151​

1096​

1115​

1105.9​

6.967384​

19​

0​

Biathlon Xtreme

357X54/500354

Yes

10​

0.865​

0.158​

0.453​

1109​

1131​

1114.9​

6.488451​

22​

0​

Biathlon Xtreme

357X54/500354

Yes

10​

1.18​

0.204​

0.664​

1098​

1126​

1112.9​

7.093816​

28​

0​

Biathlon Xtreme

357X55/504391

Yes

10​

1.504​

0.281​

0.824​

1093​

1120​

1102.3​

9.510813​

27​

0​

Biathlon Xtreme

357X55/504391

Yes

10​

1.432​

0.282​

0.76​

1091​

1121​

1102.3​

10.4142​

30​

7​

Biathlon Xtreme

357X55/504391

Yes

10​

0.741​

0.12​

0.382​

1093​

1114​

1103.4​

7.026932​

21​

2​

Biathlon Xtreme

357X55/504391

Yes

10​

1.261​

0.193​

0.726​

1093​

1113​

1103.8​

5.633235​

20​

0​

Biathlon Xtreme

357X55/504391

Yes

10​

1.324​

0.25​

0.71​

1090​

1113​

1101.9​

6.983313​

23​

0​

Biathlon Xtreme

357X55/504502

Yes

10​

1.8​

0.346​

0.941​

1090​

1111​

1102.5​

5.441609​

21​

0​

Biathlon Xtreme

357X55/504502

Yes

10​

1.978​

0.428​

1.03​

1098​

1132​

1110​

10.14342​

34​

12​

Biathlon Xtreme

357X55/504502

Yes

10​

1.746​

0.337​

0.91​

1102​

1128​

1114.4​

7.988881​

26​

6​

Biathlon Xtreme

357X55/504502

No

10​

2.2​

0.47​

1.162​

1100​

1130​

1108.9​

8.305955​

30​

18​

Biathlon Xtreme

357X55/504502

No

10​

1.125​

0.203​

0.592​

1100​

1115​

1106.8​

4.779586​

15​

0​

Biathlon Xtreme

357X54/500354

Yes

10​

1.949​

0.423​

0.993​

1111​

1139​

1121.5​

8.113774​

28​

12​

Biathlon Xtreme

357X54/500354

Yes

10​

1.885​

0.512​

0.982​

1099​

1138​

1116.9​

11.89257​

39​

8​

Biathlon Xtreme

357X54/500354

No

10​

2.305​

0.427​

1.227​

1099​

1127​

1114.8​

9.077445​

28​

3​

Biathlon Xtreme

357X54/500354

No

10​

2.082​

0.3​

1.103​

1108​

1135​

1118.5​

8.872554​

27​

7​

Biathlon Xtreme

357X54/500354

No

9​

2.859​

0.772​

1.468​

1111​

1138​

1124.111​

7.94425​

27​

0​

 

[bulletbluesky]

The mean of 5 groups mean with MV<1099 ft/s, where MV of a single shot does not exceed 1115 ft/s is 0.64.
The mean of 5 groups mean with MV>1114 ft/s is 1.15.
The ratio of these avg group is 1.15/0.64=1.8 is significant and the sample of 50 shots is high enough to give statistical significance no matter how the statistical analysis is done. The influence of chosen lots is assumed to be shared in equal proportions.
I guess with MV=1200-1250 ft/s, the avg group size* would be aprox 1.5, but with MV=1000-1050 ft/s not better than 0.5.

EDIT: avg group mean

 

[jgraves]

That's an interesting way of looking at the data.

My conclusions from looking at the data (and targets) were buy the case of 504391 and only shoot it when it's below 10*C. I would have preferred to test on a much cooler day but with the difficulty finding ammo and my availability to test, I had to take the opportunity I had available.

 

[bulletbluesky]

That's an interesting way of looking at the data.

My conclusions from looking at the data (and targets) were buy the case of 504391 and only shoot it when it's below 10*C. I would have preferred to test on a much cooler day but with the difficulty finding ammo and my availability to test, I had to take the opportunity I had available.

I agree, it would be much of use to conduct tests both in warm weather and in cool weather (with same ammo/lots and riffle). I think significant factor in the trends you see can have something to do with exit of the bullet out of the barrel and flight of the bullets further down the range through the transonic zone. Of course, special attention in the tests should be paid to wind influence which may be significant on 100 yards trajectory (very calm days in both circumstances or indoor tests)

 

[renaissanceman]

Here are some shots at 400yds yesterday using HV ammo. The fly nice and true out of the BoreBuddy Apogee Match (1:12" twist):

 

[bulletbluesky]

Here are some shots at 400yds yesterday using HV ammo. The fly nice and true out of the BoreBuddy Apogee Match (1:12" twist)

But how good compared with a good subsonic ammo up to 100 yards?

 

[renaissanceman]

But how good compared with a good subsonic ammo up to 100 yards?

HV vs Subsonic? No comparison, HV shoots worse. But it doesn't destabilize.

 

[bulletbluesky]

HV vs Subsonic? No comparison, HV shoots worse. But it doesn't destabilize.

Of course. Up to 100 yards subsonics win, after 200 yards HV win. It's understandable why HV win after ~200 yards, but not why they lose up to 100 yards (that's what we want to figure out)

 

[renaissanceman]

Of course. Up to 100 yards subsonics win, after 200 yards HV win. It's understandable why HV win after ~200 yards, but not why they lose up to 100 yards (that's what we want to figure out)

I don't think they necessarily win after 200, I think they just have a better trajectory.

 

[renaissanceman]

CCI SV at 50 from the same barrel:

Without the flier ruining the 10 shot group:

The other groups shot that day:

 

[justin amateur]

If'n y'er wanting to understand what's going on with y'er 22lr cartridges at extended range,
take a close look at them before chambering them. When the cartridges are dented, dinged,
drive bands are asymmetric, bullet is unevenly seated, visibly beat up, muzzle velocities all over,
do you really expect predictable trajectories from them? I certainly don't.
A youngster at the local range was griping about the sloppy groups he was producing at 100 yards.
I had him take a close look at what he was shooting. Pointed out just how rough those cartridges were.
It doesn't matter what the rated velocity is for that box of cartridges, if they look like they were dropped
into a pile of gravel, shaken, then boxed for shipping. Garbage in = garbage out, right?

 

[jgraves]

Targets from my Biathlon Extreme lot testing. Targets images are rotated 90° CCW (right edge of image was bottom of target).

 

[bulletbluesky]

Interesting. Looks like K group is the worst one. Among the all K doesn't have the worst MV spread, but the highest average vel. More testing is definitely needed. I remember PCC guy who noticed similar effects with 9 mm, 147 gr target ammo (I don't recall brand). From 16" carbine the best 100 yards groups were in summer, the worse in winter. In winter MV of the same ammo was almost always supersonic

 

[jgraves]

In hindsight, I wish I shot this as singles and built a composite group as it would allow correlation of velocity to POI for each shot. I've been using GRT for group analysis but plan to try OnTarget TDS for the composite group capability.

While interesting, further exploration of this ammo at summer temperatures would be purely an academic exercise (for me). My plan is to chrono at a few different temperatures indoors (20 yard range, unheated when not in use) and chrono + groups / drop at a couple temperatures at 50 and 100. I'm hoping it's good enough (or as good as 22LR gets at -20C) and I never shoot it above 20C from the Vudoo again.

I might try it in my SR-22 as it typically shoots a bit slower than my bolt guns and has done well with Biathlon Xtreme in the past.

 

[RTH1800]

Here are some shots at 400yds yesterday using HV ammo. The fly nice and true out of the BoreBuddy Apogee Match (1:12" twist):

View attachment 8267450

Please do not take this as a personal attack.

When I see this or read of “banging steel at 400 yards” it’s utterly meaningless to anyone with a technical mind.

I understand the ease and recreation of shooting metal targets. Yet technically it is of no value. Conveys zero useful data. We have no idea if you shot 500 shots to get those hits or 50 shots.

When you are “banging steel” are you shooting a 3” round or a trash dumpster. Car door?

If you want to provide useful information put up a paper target large enough to catch every shot.