leupold and bullet drop compensation

Rod Haydel

New member
I need help. I just installed a Leupold Mark 4 in a 2.5 x 8 that has BDC dials for a 7.62 168 grn. bullet. According to ballistics I can find a 168 grn bullet drop appox 4.7 inches at 200 yards and 14.8 at 300 yards if it is dead on at 100. The BDC dial shows 2 inches of compensation at 200 and 5 inches at 300. Something is not adding up here. Do I need to sight in differently? The girl at Leupold Tech assistance did not seem to know what she was talking about and just suggested I have them make some custom dials for me at my expense. Any one have any ideas here? Thanks
 
Quote:
I need help. I just installed a Leupold Mark 4 in a 2.5 x 8 that has BDC dials for a 7.62 168 grn. bullet. According to ballistics I can find a 168 grn bullet drop appox 4.7 inches at 200 yards and 14.8 at 300 yards if it is dead on at 100. The BDC dial shows 2 inches of compensation at 200 and 5 inches at 300. Something is not adding up here. Do I need to sight in differently? The girl at Leupold Tech assistance did not seem to know what she was talking about and just suggested I have them make some custom dials for me at my expense. Any one have any ideas here? Thanks



"The girl at Leupold Tech assistance did not seem to know what she was talking about..."

HA! Ain't that they truth!

The drop depends on the muzzle velocity... and what you are looking at is not the drop in inches, but the drop in MOA.

And... it says "3" on the BCD, but gives you "5" clicks - those 5 clicks are ~5 inches at 100 yds, but 15 inches at 300 yds, (and ~50 inches at 1,000 yds). Don't worry about the clicks, just dial it and shoot it.

At 2600 fps,

At 200 yds, 2 MOA is = to ~2 inches - so that's OK

At 300 yds, 5 MOA is equal to 15.75 INCHES, and that's pretty dammn close.

There is nothing wrong with the scope, it's just that you are not used to thinking in MOA and BCD dials.

At 1,000 yds, it will say "10", and (IIRC) be 37 clicks - that's 37 MOA, or ~390 inches (at 1,000 yds) .


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Keep in mind that those drop charts also change with the altitude your shooting at. If you have your scope calibrated for a certain bullet, BC and velocity you also have to specify the altitude your shooting at.

Just had a friend have that done to his 300 Rem ultra-mag. His scope is set for the one specific load he shoots out to a thousand yards and he just dials the range, but it's most accurate at the 2500 foot elevation he specified when they set the the reticle and custom knobs.
 
Barometric pressure changes your bullets BC, it can change enough under just normal changing weather to change your trajectory as much as 5 feet at 1000 yards. so you need to think about that.
RR
 
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