Temp around 65°

Cool air, warm sun.

Data was taken with garmin chrono

I tried to get groups but strong unpredictable gusts up to 30 mph in varying directions made it too difficult to isolate the ammo for consistent groups

Black hills 77 otm's red box. Unknown if this batch used the 77 sierra or the 77 hornady. All shot with suppressor. Data is avg of all strings. (3 strings 25 rounds)
High 2690 low 2622
avg 2649
Std dev 21
Ex spread 68

Black hills 69 TMK (only 1 string of 10 rounds)
High 2732 low 2683
Avg 2700
Std dev 18
Ex spread 49

Aac 75 gr w/o suppressor (1 string 10 rounds)
High 2600 low 2505
Avg 2554
Std dev 29
Ex spread 95

Aac 75 gr w/ suppressor. Avg of all strings (5 strings 50 rounds)
High 2647 low 2516
Avg 2557
Std dev 24
Ex spread 131

Now comes the part I was most excited about. I tested the badlands co 75 and 77 gr loaded in the Nas3 casings. These have given some really high velocities and I was hoping I would get similar. I was a bit let down.

75 gr w/ suppressor (4 strings 40 shots)
High 2738 low 2619
Avg 2669
Std dev 26
Ex spread 119


The 77's where similarly "slow" for what I had hoped for. (3 strings 30 shots)
High 2705 low 2571
Avg 2638
Std dev 28
Ex spread 134 (3 very low velocity shots)


If I exclude the low velocity shots I come up with
77's
Avg 2651
Std dev 18
Ex spread 84

75's
Avg 2675
Std dev 24
Ex spread 99

It should be noted that after taking out the shots that where much slower there were basically 2 velocities for the 75's. Most where within a few fps of 2650 OR 2700 the 77's didn't have the two distinct groups the 75's did.

The last test was a poi shift when the suppressor is removed. My aac 75's (what it's zeroed on) shift .75moa left and 0moa vertically

*edit* spoke with the dudes at badlands. I called strictly to give data and feedback to which they didn't find the data satisfactory. They agreed the velocities were about 75 fps slower on average then they would have guessed (should have been about 2750) and they Ex spread should have been half. Long story short they will send me some new ammo to test when i get home from this upcoming deployment, none of which I asked for. That was really cool of them.

On a side note the Nas3 ammo was felt way less gassy than the aac ammo.

Did I miss it?
PS..............  Yes, Yes I did miss it.  ;)
Sorry.

12.5 criterion. It's in the title.

Well somehow I missed NAS3 being a thing.

I read this and thought there was a chrono error or the ammo was about to explode from overpressure getting those velocities from a 12.5" barrel.

Then I Googled NAS3...

Interesting. That SD is about the same as most good AR15 ammo like Black Hills. You are not shooting a bolt gun. You are not going to find single digit SD loads for an AR15 that are not single loaded / individually weighed charges. Those velocities are about what most 16" 5.56 barrels produce.

No chrono error. This is the 4th chrono I've used with black hills and all have been consistent. I used them as a control group at the beginning for this reason

The SD is fine. The ES isn't

The velocities seem awfully fast for a 12.5 Criterion.  I have an 11.5" Criterion and a 16" Criterion, both Hybrid contour, 1:8" twist, .223 Wylde chambers.  I'm at 1,000' ASL and over past several months it was 35 - 60 degrees when I shot.  

In my 11.5", 75 gr AAC Hornady BTHP chrono close to 2,500 FPS per my LabRadar.

AAC 77 SMK chrono around 2,620 - 2,650 FPS in my 16" Criterion.  

ES and SD wasn't bad, IIRC around 30-40 ES and 15-20 ES.  

I don't have any other load info handy.

Most 12.5's chrono closer to 14.5's than 11.5's

Zero pressure issues

I have a Criterion 14.5 Core and a 16 Core. The 14.5 core shoots AAC 77 OTM around 2700 fps. Thats right around what my 18 inch WOA barrel shoots them at. The 16 shoots them at around 2650. Not sure what is up with that 14.5, but it is my most accurate barrel and my fastest barrel. The 14.5 is easily a 3/4 minute gun. The 16 is much more in line with normal velocities. I have been tempted to get an 18 inch Core just to see what it does.

My experience as well.

12.5’s rock.

I wouldn’t be quick to say never. I load on a automated/motorized progressive, and never individually weigh charges, and I often get SDs in the teens, with low teens being pretty common. The same was true on a XL750. 10 round samples. I sometimes get single digit SDs with 9mm for my PCC like this. I’m not going to say that this will match everyone's experience, just that it is possible.
Absolutely. One of the reasons I like my 12.5” barrels so much.

Edit: decided to take the Labradar with me today:
81*F

12.5” Hodge/Velos
Federal XM855
2819 fps
39 es
13.6 sd

12.5” BCM Kino/TurboK
XM855
2825 fps
69 es
20.3 sd

12.5” Criterion Core/.264 MG7k
XM855
2824 fps
31 es
9.5 sd

69gr Norma .223
2620 fps
38 es
11.1 sd