1.2 raised to the 8th power equals ~ 4.3.
1.2 X 1.2 X 1.2 X 1.2 X 1.2 X 1.2 X 1.2 X 1.2 = 4.29981696.
Which means a 1 MOA/inch group at 100 increasing 20% every hundred yards will subtend 4.3 MOA (43 inches) at 900 yards.
Get some good ballistics software (Sierra Infinity) to see how velocity and BC spread, varying cross winds, and atmospheric conditions in each 100 yard band of range. For example, a 50 fps spread with 308 Win muzzle velocity causes a 1/10" spread vertically at 100 yards; it's 20 inches at 1000. Same cartridge with a 1 mph crosswind at 100 has 1/10th MOA drift; at 1000, it a full MOA; a 10X change and winds are not constant in speed and direction throughout the bullet's path. Very little's been published anywhere about this. I've probably put more words in forums on these facts than all the others put together.
A check of benchrest aggregate group records shows them at about .2 MOA at 100 yards, .27 at 200 and 3.5 MOA at 300 yards. How's that for incremental group sizes in MOA growing as range increases? It's over a 30% increase for each range beyond 100 yards.
1.2 X 1.2 X 1.2 X 1.2 X 1.2 X 1.2 X 1.2 X 1.2 = 4.29981696.
Which means a 1 MOA/inch group at 100 increasing 20% every hundred yards will subtend 4.3 MOA (43 inches) at 900 yards.
Get some good ballistics software (Sierra Infinity) to see how velocity and BC spread, varying cross winds, and atmospheric conditions in each 100 yard band of range. For example, a 50 fps spread with 308 Win muzzle velocity causes a 1/10" spread vertically at 100 yards; it's 20 inches at 1000. Same cartridge with a 1 mph crosswind at 100 has 1/10th MOA drift; at 1000, it a full MOA; a 10X change and winds are not constant in speed and direction throughout the bullet's path. Very little's been published anywhere about this. I've probably put more words in forums on these facts than all the others put together.
A check of benchrest aggregate group records shows them at about .2 MOA at 100 yards, .27 at 200 and 3.5 MOA at 300 yards. How's that for incremental group sizes in MOA growing as range increases? It's over a 30% increase for each range beyond 100 yards.
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