I noticed yesterday that my velocity had jumped from 2912 to 2948 while getting some work done at the range. Temp yesterday was 80. Last time I was at the range with my LabRadar the velocity was in February and the temps were in the low 50s'. I'm new at this LR game and I'm curious if this is normal. 6CM AIAX running Hornady Match 108 ELD ammo. The ammo is the same batch as I had used before. It added about a tenth it seemed as I was flying over the smaller targets (6" circles) at 5-6-700. Changing the velocity in my AB app fixed the issue but I'm curious if the velocity differential seemed normal?

Just thinking on it......... could be you are seeing results of the difference in temperatures.  Metal shrinks in the cold and expands with heat.

The bore would be “smaller” when it’s cold resulting in “more” friction and subsequently less velocity.

On the other hand, the bore would be “larger” when its hot/warm resulting in “less” friction and subsequently slightly more velocity.

This as well as atmospheric pressure can give you extra velocity in warmer temperatures. That’s why you have a velocity range in your ballistic app.

The barrel has appx. 600 rounds through it and was properly broken in. My son shoots for AI and has me on a short chain as far as how to shoot this rifle. I'd be asking him this question but he's at a match and I don't want to bother him. I'm leaning toward just an atmospheric change as the culprit. I was just surprised how much the velocity picked up. I'll check it again later today here at the house and see.

OK...All is better now. I just ran a 25 round string @ 76 degrees, 1600 ft. altitude and zero wind. The SD was 9.8 with 2936 as the average speed. This tracks pretty well in my mind. This is factory Hornady Match 6CM 108g ELD ammo. I have NO idea what powder is in it. I'm done finito never again bumping shoulders, turning necks and all the other stuff that goes into true precision round hand loading. I'm older and I can buy this ammo at will. Don't ask me how. I can't shoot well enough to NEED better ammo IMHO. I'm shooting just three PRS matches this year and one is already behind me. I do this for fun and to keep my sanity in todays world lol. It's nice to know I can, on demand, shoot something at 1000 yards. Thanks for the input/help guys. I really enjoy this sport and I'd like not to embarrass my son with my shooting.