So last winter I acquired a 98 that was rebarreld to a 308 win and had alot of work done to it, when i acquired it from the estate it had a shifty scope etc. so I finally got around to mounting a scope and shooting it recently, i have some handloads from a different project that didn't work out, they were Hornady 150 sst loaded close to the top of the chart which my 99 savages did not like, this gun with a 24 inch barrel and the rock solid 98 action loves them and does what is expected, very nice grouping. For the heck of it I run three 150 grain speer rounds loaded very moderately thru it just to see how much difference, up and down was not that much difference at 100 yards but they grouped 5 inches to the left, I was expecting up and down movement not left to right, is this a normal happening, I guess when I tried this I never seen this left to right movement before. Thanks in advance for any thoughts on this.

I saw horizontal differences in point of impact of 3-4" last month when shooting varmint vs. deer loads in a Mauser. 5" wouldn't shock me.

I have trouble understanding your surprise that significantly different loads shoot to different POI's no matter which direction they are different.

Lower velocity alone, given different powders & different bullets, are not guaranteed to shift POI only up or down...............................just sayin'.,

MM

Just shows you how much barrels flop around when you go bang. And why it's important to make consistent loads with small extreme velocity spread. That gun should be a good teacher for you. Here's to an A on final exam!

In the same but opposite direction(???), I was shocked when two different people I know had no concern about going from one brand to another, without checking results on paper . . .
After all they were the same bullet weight.
One other person I know brought me his Model 70 (High Power competition gun for previous owner) and three boxes of ammo to help him sight it in.
Three different brands and 2 different bullet weights.

One should never be surprised in the location of a group from a different brand, bullet weight, loading.

Shoot it and see what it does.
Meet your predictions?

This is the reason a lot of us reload, repeatability. I have seen significant shift in poi from one lot to another of the same Ammo. And it can happen to reloaders when we change lots of powder or even primers. That is the reason we sight rifles in every so often.