You might be able to see 30 cal holes at 800 yards with a stand up tripod sized telescope, but doubtful with a typical table top shooting range styled spotter IMO....and I'd be looking at glass that started at Swarovski prices or better. Wind vibration is going to be a problem most likely too, so the unit needs to be heavy enough to stay anchored securly.
With enough money, it'll be a peice of cake.
Ron
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