Good luck on the elevation with that 'A3! (Or do you have an aftermarket rear sight on it?)
                        
You'll need a "come-up" of about 35 MOA from 200 to 1000 with MatchKing or A-Max at ~2650fps - and the issue 'A3 sight only goes up some 29 MOA from 200 to the 800 max graduation. Here's a breakdown from engineer and distinguished rifleman Bob S. -   (You need to Login

Image below shows calculated ballistics for the 175 MK at 2650 fps. "Clicks" are 1 MOA.

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