Vertical stinging with only one load

I was testing some loads for my .340 Weatherby, using three different powders. I was loading the Swaft A-Frame 225. I used IMR4350, RL19, and RL22. The first load I fired was the IMR 4350, and got a 1 inch group. I was letting the barrel cool about three minutes between shots. After shooting that group of three, I went downrange to change targets, allowing about 10 minutes until I fired the next group. I then fired the loads using the RL22 powder, allowing about 3 minutes between shots, and the group I got was a vertical string that was about 3 inches.
I let the barrel cool 10 minutes, and shot the RL19 loads, and without doing anything else, got about a .75 inch group that was a cluster (not a string).
Could one powder cause a vertical string while the other powders grouped a normal looking group? Range was 100 yards, and temp was 55 to 60 degrees.

yes

yes, but one three shot group is not enough to base a conclusion on.

I agree with Rancho, however with a 3" group with that powder and far more favorable results with the others I personally wouldn't waste my time with another try. I would take the R19 load and try to tweak that a little.

phutch30 said:

I agree with Rancho, however with a 3" group with that powder and far more favorable results with the others I personally wouldn't waste my time with another try. I would take the R19 load and try to tweak that a little.

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This.

Thanks. I do like the results so far with the R19. Not so much the R22.