.22LR Velocity Data

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HondaVTEC

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Just thought I'd share some velocity data acquired this morning . For whatever it's worth .

Conditions : 0C , no wind , bipod , No cleaning was done between ammo changes .


CZ 457 MTR 20.5" barrel

SK Standard Plus

fps SD ES AVE

1084,1088,1069,1086,1094 9.3 25 1084.2
1099,1095,1078,1084,1104 10.7 26 1092
1085,1087,1086,1086,1083 1.5 4 1085.4

SK Flatnase Basic

1096,1063,1095,1077,1099 16.6 36 1081
1092,1085,1083,1066,1081 9.6 26 1081
1090,1091.1091,1091,1092 .7 2 1092

SK Flatnose Match

1112,1093,1102,1114,1088 11.4 26 1101.8
1105,1089,1090,1093,1105 8 16 1096

Center X

1086,1096,1071,1104,1094 12.5 33 1093
1086,1087,1087,1076,1095 6.8 19 1086.2
1084,1096,1077,1095,1097 8.9 20 1089.2

SK Long Range Match

1146,1124,1126,1141,1136 9.5 22 1134.6

CCI Standard Velocity

1079,1077,1076,1112,1096 15.2 36 1086.2
1098,1107,1093,1102,1061 18.2 46 1092.2
1079,1077,1076,1112,1090 15.2 36 1086.2


Anschutz MPR 25.6" barrel

SK Standard Plus

1039,1025,1045,1045,1071 16.7 46 1045
1041,1032,1026,1039,1053 10.2 27 1038.2

SK Flatnose Match

1055,1055,1064,1077,1050 10.7 27 1060.2
1063.1051,1078,1067,1064 9.7 27 1064.2

SK Long Range Match

1086,1084,1101,1112,1111 13.3 28 1098.2
1095,1105,1105,1091,1095 6.4 14 1098.2


For whatever reason , this post won't allow things to line up correctly . Sorry

Initial Take away : The longer Anschutz barrel loses velocity . CCI SV shot awful . The first SK Flatnose Basic group was .260 ( CZ 457 MTR )
The second SK Flatnose Match group was .300 ( CZ457 MTR )
SK Long Range Match shot a .80 and 1.01 five shot groups at 100 yards ( Anschutz MPR )
 
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To make sure this data is read correctly, can you confirm the following?

Each ammo was tested in five shot strings (i.e. MV was recorded for five individual shots), followed by the SD, the ES, and the average MV. Some ammo had three five shot strings, others had two. Is this correct?
 
This is correct .

The columns were arranged perfectly when I typed this post , but , for whatever reason , when it actually posted , it jumbled everything together making it difficult to read .
My apologies .

I did not clean between ammo types and I found that for the majority of the data , the first string with next the new ammo had a higher SD and ES . Then it seemed to settle down a bit .
 
I think in formats such as those on forums, columns arranged in one way often do not remain the same once posted. As far as I know it can't be helped. The only alternative I can think of to keep columns etc. as desired is to put them in a table or spreadsheet that can be reproduced as an image.

Readers should be aware that statistically the level of confidence we can have in numbers such as SD and ES depends on the sample size of the data. In other words the larger the sample size, the greater the confidence level in the data.

A sample size of 5 shots is very small. While it's impractical to chronograph a sufficiently large enough sample size of ammo to predict its ES and SD with near 100% certainty, it is possible to increase the chances of finding data in which we can have a relatively high level of confidence.

I've been looking for a to-the-point explanation of this, but haven't been as successful as desired. Nevertheless, here's an explanation of confidence levels with regard to sample size and SD calculation by Adam MacDonald, a Canadian shooter who writes a very informative blog. It shows how a higher number of shots increases the level of confidence we can have in the data. It may take a bit to figure out what the information shows (I had to think about it for some time) but it does illustrate the point very well.

According to MacDonald,


From "Thinking Statistically" h t t p s://www.autotrickler.com/blog/thinking-statistically

Paraphrasing MacDonald, he reminds shooters that ES five shot samples can rule out a bad lot of ammo; standard deviation can prove a good lot of ammo.
 
Numbers are just numbers . It can be difficult to draw any concrete conclusions based on one time out ( like today ) . For example , one 5 shot group with "worse" numbers actually produced a smaller group . Was it me ? Was it luck ? Was it coincidence ? Who knows . What did surprise me was the effect on the printed group 25fps had at 50 yards . When a round hit low , it was always accompanied by a lower MV . It was 100% repeatable regardless of the ammo . Today also brought into focus the importance of quality ammo . This particular CZ457 MTR does NOT like CCI SV . Regardless of what the numbers show , it shot like crap every time . But , the same ammo shoots much better in my Anschutz MPR . This CZ 457 MTR with the shorter 20.5" seemed to be much more sensitive to differences in ammo compared to the 25.6" Anschutz MPR . It produced higher MV's which really showed in the POI . Faster ammo printed higher . Not really as apparent with the MPR . MV's were lower , but , it's POI was more consistent . Rimfire is a funny beast . There is no substitute for testing to see what works and what doesn't .
 
HondaVTEC said:
Numbers are just numbers . It can be difficult to draw any concrete conclusions based on one time out ( like today ) . For example , one 5 shot group with "worse" numbers actually produced a smaller group . Was it me ? Was it luck ? Was it coincidence ? Who knows . What did surprise me was the effect on the printed group 25fps had at 50 yards . When a round hit low , it was always accompanied by a lower MV . It was 100% repeatable regardless of the ammo . Today also brought into focus the importance of quality ammo . This particular CZ457 MTR does NOT like CCI SV . Regardless of what the numbers show , it shot like crap every time . But , the same ammo shoots much better in my Anschutz MPR . This CZ 457 MTR with the shorter 20.5" seemed to be much more sensitive to differences in ammo compared to the 25.6" Anschutz MPR . It produced higher MV's which really showed in the POI . Faster ammo printed higher . Not really as apparent with the MPR . MV's were lower , but , it's POI was more consistent . Rimfire is a funny beast . There is no substitute for testing to see what works and what doesn't .
Click to expand...


These are excellent observations. Numbers are only what can be made of them. I heard someone say recently, "Statistics are like Katy Perry. They reveal a lot but not everything."



The math suggests that in theory the ammo with the most smallest ES and lowest SD should be the most accurate. It's not clear if it holds true in practice. Perhaps it could be true with a perfectly uniform bore -- uniform in such factors as its chamber and leade, its rifling, its diameter, and its crown. But there are other factors of consistency and uniformity that are less likely to be measured by ES and SD, which are measurements that tell us about the uniformity and consistency with which the bullets leaves the muzzle.

ES and SD figures are data that is often calculated close to the muzzle, not downrange where the bullets ultimately strike the target. Disregarding wind as a factor, the chrony data is less likely to reflect other important factors at play in the quest for accuracy. ES and SD reveals little if anything about bullet concentricity or runout and it reveals less about rim-to-ogive consistency. Both of these are important factors in .22LR accuracy.

Can ES and SD accurately predict accuracy? No, not necessarily. They can, however, be a tool to help explain the results on target.
 
Based upon the data acquired yesterday , I took a run at the 50 yard Challenge this morning using SK Flatnose Basic with the CZ457 MTR . .216 ,.251 , .410 , .500 ,.500 . The wind came up for the last 3 groups and I almost lost it . 5 group average was .375 . 16X and a bipod . Not pretty , but , it's there :)
 
HondaVTEC said:
Based upon the data acquired yesterday , I took a run at the 50 yard Challenge this morning using SK Flatnose Basic with the CZ457 MTR . .216 ,.251 , .410 , .500 ,.500 . The wind came up for the last 3 groups and I almost lost it . 5 group average was .375 . 16X and a bipod . Not pretty , but , it's there :)
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When your group opened up, was it vertical spread (velocity changes) or lateral spread (wind). When you're measuring ammo for consistency you can almost ignore the wind because you're worried about vertical spread, n'est ce pas?
 
The spread was all horizontal . I saw the wind come up but I was almost out of time so I just shot through it the best that I could . I mean , who cares right ? It's not a bench rest Match rifle so I don't expect perfection . Certainly not with lower cost ammo . It's an off the shelf factory rifle shooting lower cost ammo . It is what it is :) It made the list so I know it CAN do it , but , not as pretty as the Anschutz . I'll try again on another day when it warms up a bit and use better ammo to see if I can improve it's performance . The guy sitting 10 feet away blasting away endlessly with a 7.62 x 39 SKS didn't help the concentration factor either :)
 
HondaVTEC said:
The spread was all horizontal . I saw the wind come up but I was almost out of time so I just shot through it the best that I could . I mean , who cares right ? It's not a bench rest Match rifle so I don't expect perfection . Certainly not with lower cost ammo . It's an off the shelf factory rifle shooting lower cost ammo . It is what it is :) It made the list so I know it CAN do it , but , not as pretty as the Anschutz . I'll try again on another day when it warms up a bit and use better ammo to see if I can improve it's performance . The guy sitting 10 feet away blasting away endlessly with a 7.62 x 39 SKS didn't help the concentration factor either :)
Click to expand...

I usually bring a braked .375h&h with me for those fellows :)
 
HondaVTEC said:
The spread was all horizontal . I saw the wind come up but I was almost out of time so I just shot through it the best that I could . I mean , who cares right ? It's not a bench rest Match rifle so I don't expect perfection . Certainly not with lower cost ammo . It's an off the shelf factory rifle shooting lower cost ammo . It is what it is :) It made the list so I know it CAN do it , but , not as pretty as the Anschutz . I'll try again on another day when it warms up a bit and use better ammo to see if I can improve it's performance . The guy sitting 10 feet away blasting away endlessly with a 7.62 x 39 SKS didn't help the concentration factor either :)
Click to expand...

I think you are underestimating the mtr. Mine would shoot lights out all day, with sk match. I ran matches all summer and it outshot a lot of guys with some nice guns. I didn’t like the 16 inch barrel and really wanted the Bergara so I dealt it. Wish I could keep them all but I cannot, after a year I wanted a change. On a nice day in the summer you will see a lot of really small groups
 
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