I say 100 & 300 because your 100m group will be small enough to get a good idea where it is and you've got enough leverage to estimate trajectory difference . Not so much drop between 200 and 300 and you won't be able to pinpoint the groupp centre so well at 200. Ranges dont have to be exactly 100 and 300 as long as you know exactly by rangefinder what they were. Eg 67m and 284m would be fine. Shots on paper will also tell you how far you can realistically hit something under favourable conditions. Take a minute to look where the shots fall in your reticle at max mag too and write it down.. who's getting carried away now ?
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