How to open military boxes in Revelations 2

This is for anybody who is having trouble unlocking the military/gimmick boxes in Resident Evil Revelations 2. I'm sure there are better and faster methods to doing this, but this is how I've been doing it and its been pretty reliable so far especially for those timed boxes in episode 3. It requires a little bit of guestimating and isn't exact, but basically you have to ascertain the X and Y coordinates to zero in on the location of the hidden circle. The more you pratice it, the faster you can do it. Good Luck.

RESIDENT EVIL® REVELATIONS 2
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