Do you have two boxes, if so what does the label say about the Muzzle Velocity. If the velocity is the same, then so are the two cartridges to a degree. If they are from the same lot, they are the same, if not there could be subtle differences that could account for some variation. The difference you experienced, did you shoot them side by side, or at different times, esp. winter vs. summer.
From what I've observed:
Black box (tactical) is loaded in Lake City stamped brass and has crimped primers. (possibly military overrun/reject/using up the last of a batch of components?)
Red box is loaded in "federal" stamped brass and is not crimped.
This is anecdotal and you may find exceptions to this.
To make things more confusing, my LGS has recently had blue boxed American Eagle.
From what I've observed:
Black box (tactical) is loaded in Lake City stamped brass and has crimped primers. (possibly military overrun/reject/using up the last of a batch of components?)
Red box is loaded in "federal" stamped brass and is not crimped.
This is anecdotal and you may find exceptions to this.
My black box and red box stuff both have the same stampings
I think the blue box has proceeds going to fallen police officers?
Like this stuff?
Like this:
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Never seen that one before......
From what I've observed:
Black box (tactical) is loaded in Lake City stamped brass and has crimped primers. (possibly military overrun/reject/using up the last of a batch of components?)
Red box is loaded in "federal" stamped brass and is not crimped.
This is anecdotal and you may find exceptions to this.



























