You can never count on any two different rounds impacting the same. Often they will be close, but it isn't always a guarantee.
There are too many factors that go into play but here are a two that come to mind:
-Bullet Weight, Shape, Bearing Surface, etc. affect mv and retained velocity as well as bullet stability)
-Powder, obviously different powder charges affect mv, but different powders are affected by temperature at different rates too. Two loads that might shoot identical at high temps might not at low temps.
In my hand loads, I sometimes see a POI shift, not only in elevation, but in windage with just a couple .1's of powder variation or .01's of seating depth.
Rimfires are a whole different game, but as an example, I have seen a POI and accuracy difference in different Lot No. of the exact same brand/type of ammo.
I was doing some load work with a buddy last year and we played with several different types of ammo and a variety of hand load work-ups. At 100 yards, some of the factory loads shot as well as 1' to 3/4", while some shot groups in excess of 3". For reference, the right hand loads with this gun are around 0.6". Every type had a different POI. I don't recall any being as much as 6", but definitely 3" to 4". I think short barrels and gas operated guns may exaggerate this too. I'm not sure what affect the can might have, no experience there.
Glad you got it figured out and put three dogs down though!