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300 meters is doable here is a video of me plinking at a steel target at 300 meters, limit of my range. Standard velocity work much better at longer ranges. The high velocity and hyper velocity work well out to 100 yards or so.
I would suggest zeroing at whatever range you want to shoot at. I zero at 50 yards, 100 yards 200 yards and 300 meters. A sightron is a good scope you should have no problem going up and down in elevation and retain your zero.
also temperature, pressure, wind, a butterfly's fart will affect zero on a 22lr.