- Thread starter dntworry
- Start date
For "good numbers" I look for single digit SD's and ES's under 30. Though, it's not easy to find lots that can consistently get ES's under 30.
For CCI SV's , you might expect to see ES's around around 40ish, which is really pretty good for ammo at its price point bad and very nice for practicing.
I guess it depends on how many rounds you fire.
LabRadar data from 11/18/2018
62.3 Degrees
40.5 Humidity
29.03 Pressure
866 Altitude
1609 Density Altitude
Savage B22 FV-SR using CCI SV (50 rounds) :
Stats - Average 1070.95 fps
Stats - Highest 1102.44 fps
Stats - Lowest 1039.96 fps
Stats - Ext. Spread 62.48 fps
Stats - Std. Dev 13.73 fps
LabRadar data from 11/18/2018
62.3 Degrees
40.5 Humidity
29.03 Pressure
866 Altitude
1609 Density Altitude
Savage B22 FV-SR using CCI SV (50 rounds) :
Stats - Average 1070.95 fps
Stats - Highest 1102.44 fps
Stats - Lowest 1039.96 fps
Stats - Ext. Spread 62.48 fps
Stats - Std. Dev 13.73 fps
No doubt about that.
And just how good one's chrono is can be a significant factor as well. Just like it only take just one bad cartridge to throw off the numbers quite a bit, like when it comes to ES's and/or just not shooting enough rounds to give one a reliable SD.
I typically take measurements in 10 round sets and record it all on a spreadsheet. Then on that spreadsheet I can easily calculate a large number of firings . . . like the following for my last 100 rounds of CCI SV's (as a comparison to your numbers):
My last 100 rounds:
Average 1093.7 fps
Highest 1129 fps
Lowest 1068 fps
Ext. Spread 61 fps
Std. Dev 11.42 fps
The last 50 rounds:
Average 1093.7 fps
Highest 1129 fps
Lowest 1069 fps
Ext. Spread 60 fps
Std. Dev 11.42 fps
The Previous 50 rounds:
Average 1093.8 fps
Highest 1122 fps
Lowest 1068 fps
Ext. Spread 54 fps
Std. Dev 11.34 fps
The Last 30 rounds:
Average 1093.5 fps
Highest 1108 fps
Lowest 1069 fps
Ext. Spread 39 fps
Std. Dev 11.33 fps
*One of the best 10 round sets:
Average 1090 fps
Highest 1101 fps
Lowest 1080 fps
Ext. Spread 21 fps
Std. Dev 5.6 fps
One of the worst 10 round sets:
Average 1099 fps
Highest 1129 fps
Lowest 1075 fps
Ext. Spread 54 fps
Std. Dev 15.2 fps
The Chrono used for these was a Magnetospeed V3
Rifle: RPRR with 18" Shaw match SS barrel
Environment conditions varied a little . . .
Temp ranged from 80°F to 95°F
Humidity from 20 to 35%
Altitude @ 880
* Best was measured in an temperature experiment where cartridges (not the environment or barrel) were at 40-45°F and environment was at low 90's°F
Last edited:
One of the nice things about the LabRadar is that it creates an Excel file for each series. You can start a new series at anytime (i.e. - 10 round or 50 round sets).
It also creates an Excel file for each shot in the series including the time in seconds, velocity, distance,and SNR (signal to noise ratio). If I see any suspect values in a series, I can look a the SNR to give me an idea if the data is valid. The shot spreadsheet shows values roughly every .002 seconds. With standard velocity ammo, that's more than a reading every yard out to 100 yards.
It also creates an Excel file for each shot in the series including the time in seconds, velocity, distance,and SNR (signal to noise ratio). If I see any suspect values in a series, I can look a the SNR to give me an idea if the data is valid. The shot spreadsheet shows values roughly every .002 seconds. With standard velocity ammo, that's more than a reading every yard out to 100 yards.
The Magnetospeed V3 does essentially all that for recording series for an Excel file . . . except of course, it doesn't get those values down range. That's where LabRadar really shines (once it's set up where it can pick up reading on a small round like a .22LR
). For my RPRR, I've got it set up where it's not attached to the barrel, but is attached with an extension I jury rigged to the hand rail. It takes about 5 minutes or less to get it all out of the box and set up ready to go. And so, I never have to worry about any POI shifts and just about mount it every time I'm firing at the range.
Typically, I set it t "8" when mounted on my RPRR as it's just a little lower below the bore than recommended. When on my other .22's, I typically set it at "6".
Here's an old pic when I first got the RPRR and set up the Magnetospeed.
A few changes since:
