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Dunno, ive half given up on it ha ha. Mate used it last weekend and said it got quite close to validated speed after he had been shooting for a while. I just think its shit

A way i found good was to zero at 100 and then shoot a group at say 300 without dialling at all. Measure the drop, tutu with speed in the ballistic app to get the same drop then check at further...

Cant beat actual real data :D

Matt I have one, seems to be way out until it warms up? You had any similar issues? Mines about 80fps out when cold.