Hornady 270 130gr. sst vs. 140gr

Recently went to the range with a box of 130gr. and 140 gr. sst hornadys. These are factory loads from hornady in the box marked custom, not the superformance. My rifle was sighted in 2 inches high at 100 yards for 130 grain bullets. Shot the 130gr. ssts first very happy. Five shots measuring .862 outside to outside out of a gun vise. Right at an inch from the bipod...not bad for factory ammo and 100 degree heat. Now the 140s another story. Fired my first shot. Nothing, no green showing from he shoot and see target. Tried again, same result. Now I was really scratching my head. Put up a bigger target behind my main target, and went for broke with a six shot string not seeing anything on the shoot and see. Went and checked the target, and the 140s were shooting almost 10 inches low and 3 inches left. With all six of the shots no further than 1.5 inches apart from a very hot barrel at that point. Just to make sure nothing was loose. I went back to the 130s, all were right on 2 inches high.

My question is is it normal for a 10 grain increase in bullet wieght to have such drastic point of impact changes? The ammo grouped well, but that low at 100 yards really has me wondering. Also, the results were almost identical at 200 yards, just a little lower.

A bit unusual to move that much, but none the less possible. There may be other factors beside the bullet involved also. The primers might be different. So could the powder type and weight. The 130 grain load might hit a totally different node.