Met up with Doco Overboard & his charming Mrs, who's become friends with my Mrs, And One of their sons.

Had a really pleasant day, still messing with the 22 sub caliber tubed SMLE he fitted for me, & the box of Sub Sonic CCI.

Interesting results.

Wind was a problem from 7 O 'clock & gusting from 5~15 MPH. Not to much for the bullets @ 25 Yds, but for the the dB meter which kept picking up wind noise variably from 5 to 23dB!

This barrel, Measured from closed., locked bolt face to muzzle Is 26" No wonder it's fairly quiet & a bit nippy even with subsonic!

Velocities were interesting.

CCI Mini-Mag 1189FPS +/-54 FPS

CCI Std Velocity 1046 FPS +/-22.08 FPS [EDITED]

CCIn Sub-Sonic 1031 +/-15.57FPS!

From today's temps & pressures That's

CCI Std Vel 0.92 Mach

CCI Mini-Mag 1.052 Mach

CCI sub sonic .091 Mach.

I only heard the double report with the Mini-Mag! Not sure if that's wind carrying away, the impact noise, or sonic boom! I'm leaning towards the latter.

Pizza for lunch was nice too. Its our turn next time mate We'll crank up the BBQ whenever you wont to drop over & your son too.

It’s surprising that there was little difference in mean velocity between the standard and sub-sonic CCI, but the former has a very high ES. Old .22 ammo? 

The ES was a bad data point I missed.

Once I deleted that & recalculated it dropped a lot.

One round either clocked the muzzle blast or was a left over from a previous session @2303.51 FPS! discarding that entry recalculates as Avg of 1046 FPS +/-22.08 FPS! a lot more reasonable.

I had a target up @ 25 yds but was really only using it as a check aim point so I didn't shoot the chrony. The "Group" (more like a pattern,) of 42 rounds was about 3" X 2" with a little vertical stringing. Not really surprising as I was firing 4 different kinds of ammo. Remington Thunderbolts, CCI Mini-Mags, CCI Std Velocity & SSI Sub Sonics!

Interestingly, the group centered 3" high, 2" left from the basic zero I determined last time there!

The Chrono is a "Shooting Crony Beta Master" with the hard copy printer accessory.

I recently picked up a Garmin Xero C1 doppler radar chronograph and I'm very interested in setting it up with my Oehler to see if there's any difference between the two.  Hopefully they both read fairly close because if they don't, how do I figure out which one is off?  Set up a 3rd chrono?

Yes, the optical units are subject to variables like lighting quality, volume & angle.

I normally use the overhead screens all the time simply because they are consistent.

Chrony actually made a rather mickey  mouse overhead lighting unit for poor or indoor applications.

I fabricated a similar unit but with LED lights on a DC power supply or "9v Radio battery" supply so no "flickering" effects.

The ONLY test is as you suggest a third check chrony, preferably one with the third "proof" sky-screen. those are the "gold Standard."

Latest test

I found some CCI "Quiet" & a box of Dynamit Nobel subsonics, so I ran them through the mill in my quest for how low can you go on the SMLE.22 tubed rifle.

interesting results.

Both are very "discreet" & with 695 & 709 FPs velocities respectively.

Firing signature is now down on a par with my Webly Hurricane air-pistol & a 40 Gr pill at 700FPs more or less is certainly adequate for anything I'm going to need.

Sorry we missed you up there the other day Sham....

Like another forum-er, my dad passed away a few weeks back and we've been in sort of a rut.

Not to mention we got tied up with some things that we've been putting off around all of that. So, were just starting to get caught up.

And, nothing seems to work out right. You know, start- stop. Get everything moving and this and that pops up etc. Our timing has been 180 degrees out around here lately.

Hope to see you guys soon.

No worries. 

Our Condolences to you & your Mrs, take care of family first.