22 LR Long Range Dispersion, What is the Culprit

[padom]

What do you attribute this to? It is generally discussed as a difference in velocity

My findings have been exactly as you say, velocity.

My most consistent results from 200 - 400yds has been with RWS R50 which has a higher velocity than all the Lapua/SK offerings and lots I've tested.

R50 and RWS Special Match are consistently at or above 1100fps with low single digit SD's. RWS takes a lot lore lot testing to find a good lot unlike R50. This has been consistent across all the barrels I've tested.

Lapua and SK offerings have always been in that 1050 - 1075 range with some outlier lots seeing as low as 1025 and as high as 1085. 90% of the barrels I've tested have been 20" but I've tested everything from 16" - 26" and twists from 11 to 16.5..

 

[Jpete]

My findings have been exactly as you say, velocity.

My most consistent results from 200 - 400yds has been with RWS R50 which has a higher velocity than all the Lapua/SK offerings and lots I've tested.

R50 and RWS Special Match are consistently at or above 1100fps with low single digit SD's. RWS takes a lot lore lot testing to find a good lot unlike R50. This has been consistent across all the barrels I've tested.

Lapua and SK offerings have always been in that 1050 - 1075 range with some outlier lots seeing as low as 1025 and as high as 1085. 90% of the barrels I've tested have been 20" but I've tested everything from 16" - 26" and twists from 11 to 16.5..

What do you consider as an ideal twist rate for 200 - 400 yards? I recently tried the Norma Long Range and it is of higher velocity than Lapua but was not near as accurate.

 

[CharlieNC]

My findings have been exactly as you say, velocity.

My most consistent results from 200 - 400yds has been with RWS R50 which has a higher velocity than all the Lapua/SK offerings and lots I've tested.

R50 and RWS Special Match are consistently at or above 1100fps with low single digit SD's. RWS takes a lot lore lot testing to find a good lot unlike R50. This has been consistent across all the barrels I've tested.

Lapua and SK offerings have always been in that 1050 - 1075 range with some outlier lots seeing as low as 1025 and as high as 1085. 90% of the barrels I've tested have been 20" but I've tested everything from 16" - 26" and twists from 11 to 16.5..

I recently purchased SK Long Range Match which is advertised at a little over 1100, and the initial shots at 50yd looked pretty good, and will stretch it out next time at the range. It's the highest velocity I've tried so far.

 

[padom]

I recently purchased SK Long Range Match which is advertised at a little over 1100, and the initial shots at 50yd looked pretty good, and will stretch it out next time at the range. It's the highest velocity I've tried so far.

I have not tested any SK Long Range but have heard good things about it when lot tested. I have zero data on it though.

 

[padom]

Here's some notes from a recent lot testing session @200yd over my Garmin with a 20" Green Mountain RimX barrel.

All the RWS was right at 1100 or higher and the CenterX was under 1080.

Was a windy session but 10 shot 200yd RWS groups were under 1.5"

https://imgur.com/lVsowNd

10 shot groups @ 50yds

https://imgur.com/dj1uEDN

Lot testing @ 100yd with this GM barrel 5 shot groups (2 lots of R50 bottom row shot best)

https://imgur.com/Arjguxq

200yd windy shooting conditions

https://imgur.com/uzjupUv

https://imgur.com/O1iDVgE

400yd sub 3.5" group FGMM UltraMatch 20" Bartlein 1:16 from bench with rear bag in the snow

 

[padom]

Here another lot test on a 20" Bartlein RimX barrel

https://imgur.com/u7dNQXF

 

[padom]

What do you consider as an ideal twist rate for 200 - 400 yards? I recently tried the Norma Long Range and it is of higher velocity than Lapua but was not near as accurate.

Honestly, a lot of talk out there about faster twist being better for long distance 22LR shooting. Ive tested 11, 12, 13, 15, 16 and 16.25 from 50 - 500yd.

In all my testing, I found the faster twist 11 and 12 twist barrels to shoot worse at 50 and 100yd and no better or worse than my 16 and 16.25 twist barrels at 200-500yd.

So to answer your question, I shoot 16 twist and find it the best twist for all distances.

 

[SteveUrban]

Wouldn’t ES of a minimum 10 shot group be a better indicator of actual performance than SD?

 

[padom]

Wouldn’t ES of a minimum 10 shot group be a better indicator of actual performance than SD?

Repeatable, consistent group size at the intended distance is my performance indicator. Everything else is just recorded data for multiple data points for comparison from one lot to the next. I record all data, including ES.

 

[SteveUrban]

Repeatable, consistent group size at the intended distance is my performance indicator. Everything else is just recorded data for multiple data points for comparison from one lot to the next. I record all data, including ES.

Would not a low ES translate to less vertical dispersion? I only shoot to 200m with the 22lr for BPCR Silhouette. The old Federal 900 I shoot has a ES of 33 for 10 shots, good enough for me at that distance. With full bore BPCR, a ES of 10 fps or less is what is desired to reduce the vertical. I used to be hung up on low SD’s, but after shooting big chunks of slow moving lead I have learned that ES is a better indicator of how a load will perform.

Cheers,
Steve

 

[grauhanen]

No matter the ES, MV is not a consistent predictor of POI. MV/POI mismatch is not an infrequent characteristic of many lots of .22LR match ammo. The further the target the worse it can be.

 

[Will Henry]

No matter the ES, MV is not a consistent predictor of POI. MV/POI mismatch is not an infrequent characteristic of many lots of .22LR match ammo. The further the target the worse it can be.

Likely the result of variances in barrel time? It is possible to have identical velocities with differences in barrel time. Kind of like two cars both doing 100 mph in 1/4 mile but one taking less time to do it. WH

 

[CharlieNC]

I've stretched the 22lr out to 300YD on a few days so far, primarily using the SK Long Range ammo. Max dispersion is clearly due to the wind, surprise - surprise. Vertical dispersion is around 4", the wind moves it 5" - 15+". While inherient accuracy is pretty good. at that distance the wind dominates and it is no longer a symetric cone of dispersion.

 

[TRSR8]

LMAO. We let the targets decide if a barrel is broken in yet. Cut rifled Kriegers and Bartleins have shot lights out 0.1 AGG's @ 50 from the start while button barrels have taken 500-1000rd to tighten up and break in.

We have some barrels with 5000rd+ on them and we have some barrels only tested for 500-1000rd.

Your post is laughable at best.

His post might be laughable….. your group measurement is embarrassing.
Still haven’t figured out a group with space between two holes cannot be less than bullet diameter, such as your .1” agg claim based on absurd measurement.

 

[padom]

His post might be laughable….. your group measurement is embarrassing.
Still haven’t figured out a group with space between two holes cannot be less than bullet diameter, such as your .1” agg claim based on absurd measurement.

Lol, its very simple. Outside to outside black smudge minus 0.223. If you want to subtract a different number add 0.223 to the measurement and subtract whatever number you choose. This is pretty standard measuring practice not something I just magically made up on a whim.

 

[TRSR8]

Lol, its very simple. Outside to outside black smudge minus 0.223. If you want to subtract a different number add 0.223 to the measurement and subtract whatever number you choose. This is pretty standard measuring practice not something I just magically made up on a whim.

.223, absolutely fine. Given that, two holes exactly touching would measure .223”, paper in between holes would be larger….,you better check your claimed .1’s again, and FWIW , i’ve beet a group shooter a long time.

 

[grauhanen]

Given that, two holes exactly touching would measure .223”, paper in between holes would be larger….

This is an undeniable fact.

To illustrate for readers in general, below is an example of two holes touching. It uses a bullet hole size of .22". The two holes are .220" center-to-center. When any space appears between two holes they must be further apart than when just touching. The example to the right shows three holes just touching. The farthest apart are .440" center-to-center.



There's a simple explanation for why some groups can be measured smaller, for example two holes just touching measuring less than .220". The actual size of the bullet hole in the target paper is usually less than .220" (or .223").

If the actual bullet hole is smaller than the size used for subtracting from the outside group size, a smaller measurement will be the result.

Below are two measurements of the same bullet hole. The first shows the measurement of the actual bullet hole, including the grey smudge. It will vary according to paper used, but in this case it happens to be .205".

If two of those holes were just touching each other, they would measure on the outside at .205 + .205 = .410". Subtract .220" from that would give .190" ctc. But we know that the two holes just touching would be .205" ctc.

At bottom is the same bullet hole with the calipers showing .220" which is clearly too generous.

 

[TRSR8]

Great explanation,…spot on . We might argue about two touching could be .200”, .190”, etc. but two not touching sure as hell wouldn't be a .120”, .150”, .180” or anything remotely sub .200’s.
If we’re going to publish facts, how about if they’re remotely factual.

 

[padom]

Numerous rimfire matches over the years measure this very way of measuring outside to outside black smudge and then subtract 0.223. I didnt invent this method or pull it out of my ass.

We have continued using that method over many years and large amounts of rimfire data which keeps comparison between group size consistent when comparing data from different barrels and ammo lots.

If that hurts your feelings or gets your panties in a bunch then you can move on. Nobody here is claiming to have broken world records or looking for awards or prizes.

I'm not changing my method of measuring a group or demanding anyone else change their method because you said so.

Like I said before. If you want the outside to outside back smudge measurement add 0.223 to any group I've posted then do what you want from there.

 

[TRSR8]

Nobody is questioning the methodology sport, what is being questioned is the fact that you simply don’t know how to apply it, making yourself look far better than the holes show, so you can “ ha ha ha” all you want.
Perhaps you should simply declare them them zeros.
Some guys shoot groups in competition on a regular basis, if you’re going to publish info, then beat your chest about it, the least you could do is be somewhat accurate about it
Gotta get me a set of those Snipers Hide calipers, I guess.