The world record for the longest-confirmed sniper kill has just been broken

Confirmed kill range 3.450 meters ( 2.14 miles ) is pretty impressive. This way outranges anything we were ever taught in school. Does anyone have any further details re rifle, scope, ammo, other factors making this kill possible? Is this pure luck - or can modern equipment, personnel, and training deliver consistent kill at this range? Warmest Regards, Sandy :)

p.s. The rifle was reported to be McMillian TAC-50 Canadian Service Rifle Designation C15A1 with 750 grain Hornady A-MAX Very Low Drag Bullets. The standard issue sight is a Schmidt and Bender 5-25X56, which is a $4000 digital optic on a $10,000 rifle. One published analysis suggests to me this may be pure luck. But, I am certainly not an expert - and really wonder whether such calculations and precision may be repeatable. "Making the assumptions that the sniper was using US military M33 ball ammunition with a 647 grain bullet (nearly 42g), and with the average temperature, altitude and humidity data for Baghdad at the beginning of June (30 deg C, 34 metres and 21 per cent humidity, respectively), a muzzle velocity of 3,000ft per second, and a scope height of an inch and a half over the centre of the bore, we can estimate that a range of 3,750yds – near enough the 3,773yds at which the shot was taken – the sniper had to correct his sights and aim off by more than 12 thousand inches, or 327 arc-minutes of angle, to compensate for the drop of his bullet over such a great distance. The bullet was in the air for 9.7 seconds."