Broncazonk
When the 7mm talks: the conversation ends.
From Wiki: "...non-C.I.P. conforming British military issue overpressure .338 Lapua Magnum cartridges with a 91.4 mm (3.60 in) overall length, loaded with 16.2-gram (250 gr) LockBase B408 very-low-drag bullets were used in November 2009 by British sniper Corporal of Horse (CoH) Craig Harrison to establish a new record for the longest confirmed sniper kill in combat, at a range of 2,475 m (2,707 yd)."
I don't doubt the record (the yardage) I'm just trying to figure out how CoH Harrison made the shot. Assuming the "non-CIP ... overpressure" .338 Lapua round yielded a generous 3,100 fps at the muzzle, (nominal velocity 2850 fps) the 250 gr. bullet had a G7 BC of .314 (250 gr. MatchKing) and he made the shot at 9,000 feet in elevation at 45-degrees, the bullet does not arrive supersonically--it's not even close. JBM has the bullet going subsonic at 2,200 yards which is 500-yards short of the target.
According to Wiki: http://en.wikipedia.org/wiki/Craig_Harrison_(sniper) the shot was made at 3,422 feet in elevation, so all things being equal, the bullet went subsonic at 1800-yards which is 900-yards short of the target, and when the bullet arrived, it was only going 859 fps.
According to Wiki (which used slightly different numbers
"The external ballistics software program JBM Ballistics predicts that the bullets of British high pressure .338 Lapua Magnum cartridges using 16.2 g (250 gr) Lapua LockBase B408 bullets fired at 936 m/s (3,071 ft/s) muzzle velocity under International Standard Atmosphere conditions at 1,043 m (3,422 ft) elevation (air density Ï = 1.069 kg/m3) and assuming a flat fire scenario (a situation where the shooting and target positions are at equal elevation) and a 100 m (109 yd) zero (the distance at which the rifle is sighted in) arrive at 2,475 m (2,707 yd) distance after approximately 6.017 seconds flight time at 251.8 m/s (826 ft/s) velocity and have dropped 120.95 m (396.8 ft) or in angular units 48.9 milliradian (168 MOA) on their way.
He walked the range in with nine (9) rounds, the tenth (10) was on the money, but how did he do it? The bullet was unstable for 900-yards and he wasn't even in the scope--he would have needed 46 mil of adjustment to get there--and the S&B PMII 5-25x56 don't got it.
Bronc
I don't doubt the record (the yardage) I'm just trying to figure out how CoH Harrison made the shot. Assuming the "non-CIP ... overpressure" .338 Lapua round yielded a generous 3,100 fps at the muzzle, (nominal velocity 2850 fps) the 250 gr. bullet had a G7 BC of .314 (250 gr. MatchKing) and he made the shot at 9,000 feet in elevation at 45-degrees, the bullet does not arrive supersonically--it's not even close. JBM has the bullet going subsonic at 2,200 yards which is 500-yards short of the target.
According to Wiki: http://en.wikipedia.org/wiki/Craig_Harrison_(sniper) the shot was made at 3,422 feet in elevation, so all things being equal, the bullet went subsonic at 1800-yards which is 900-yards short of the target, and when the bullet arrived, it was only going 859 fps.
According to Wiki (which used slightly different numbers

He walked the range in with nine (9) rounds, the tenth (10) was on the money, but how did he do it? The bullet was unstable for 900-yards and he wasn't even in the scope--he would have needed 46 mil of adjustment to get there--and the S&B PMII 5-25x56 don't got it.
Bronc