.22 Ammo for 'Calibrating' Chronograph

[Bongo Boy]

Just wondering what range of velocities I should expect from standard velocity, non-match .22 LR ammo fired from the same gun, and what typical SD values are that you get with say 20-30 rds.

I don't actually have a .22 anymore, but I'm sure I could borrow one. What might you expect for quality factory handgun ammo such as .45 ACP--should 25 rounds have velocities within 5% of one another, or be even better than that?

[Cy Soto]

About a week ago I took my chrono to the range to try out some loads and, since I had my Buckmark with me, I decided to run a ten rounds of .22LR through the chrono to see what sort of results I would get. I was shooting Remington Bulk-Pack ammo (36gr). I don't remember the exact values but the velocities where in the neighborhood of 1,100 FPS with an ES of something like 70 and an SD in the mid-20s. This is definitely not match-grade ammo by any stretch of the imagination... I imagine that if I was running ELEY or Lapua ammo through a rifle my results would have been more consistent.

[kgunz11]

I've seen Eley Tenex run 5 fps ES over 20 rounds fired. Pretty amazing stuff. I use to shoot 22BR and we would pick ammo that came off a certain machine with a certain powder lot based on the temp and humidity on match day.

So what's the process for calibrating a match chrono? I've owned a lot of chrono's in my days and the only one I trust is the PVN-21. The thing is simply amazing.

[G-ManBart]

Yeah, even CCI-SV shows pretty high ES And SD when shot through a pistol (haven't tried it through my rifles over the chrono). You'd almost definitely have to go with Tenex or maybe Match black box or high end Lapua. I've got some Tenex...might have to try it over my chrono. Problem with that is it's as expensive as centerfire

[LPatterson]

Testing 22 Federal & Remington bulk pack through 3 different guns has shown a difference of up to 30FPS ES between 2 groups of 10 shots in the same gun with the same ammo. ES for a 10 shot group ranged from 62FPS in a Beretta U22 with Federal to 115FPS with Remington while in a Ruger MK 2 Competition Target it was 80FPS with Federal to 108FPS with Remington. I have results for several different brands of 100 round boxes through 4 different guns and the analysis appears to indicate 40gr bullets have less extreme spread.

[gm iprod]

For checking my chrono I use a rifle not a handgun. Most 22lr ammo is designed for 16"+, not 5" or 6".

I use a CZ452 or my BSA Intl. As for ammo. I try to keep to stuff that I know is more likely to be available again. Win T22, CCI Std and Fed Gold Medal 711B, my BSA shoots that into 1" at 100yards, so I figure it is consistant enough for me.

Keep a record of the calibration so that if you have to switch to your backup ammo you know what that did last time out.

[Team Amish 1]

Last time I logged some .22LR in my chrono spreadsheet, I had these results.

Quite a spread.

Date: 1/1/10

Temp.: 50°F

Gun: S&W 617, 10round, 6" barrel

Ammo: 36gr HP Federal 550rd bulk from Wallyworld

FPS --- PF

1064 --- 38

1077 --- 38

1038 --- 37

1033 --- 37

1028 --- 37

912 --- 32

998 --- 35

1023 --- 36

1010 --- 36

1048 --- 37

Edited June 17, 2010 by Team Amish 1

[Heggis]

Couple of different speed from few months ago...

http://heggis.kuvat.fi/kuvat/Guns/Browning%20Buck%20Mark/buckmark_speeds.jpg/full

I'll propably do another speedtest in summertemps...