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Question about a Nikon Prostaff... |
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bbush
Optics Apprentice Joined: October/12/2008 Location: Mississippi Status: Offline Points: 93 |
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Posted: October/19/2008 at 10:31 |
I am trying to decide about getting a Nikon Prostaff scope with the BDC recticle. Does anyone know how much drop each one of the circles below the center is calculated for. In other words, the the first circle below the center allows for X or XX inches below center. The second circle allows for XX below center and so on. I know that the idea is that the first circle should be pretty much on at 200 yards for most standard rifles (if zeroed at 100 yards), but it set up for a certain number of inches below center...what are the measurements for each one of the circles. I am trying to decide if it would be even worth fooling with for a 45/70 or any caliber that has a rainbow trajectory. If I know the measurements for each circle, I could look at a ballistics trajectory calculator and see at what yards each circle would correspond to. Thanks for all input back.
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Big Squeeze
Optics Master Extraordinaire GOOGLE NINJA Joined: August/30/2007 Location: Anaheim, Calif. Status: Offline Points: 3143 |
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I wouldn`t mess with a BDC reticle, especially for use atop a 45/70. The circles are simply guidelines for trajectories, but not absolute in any way. They are too busy for my taste.
You`ve got a powerful, short to moderate range hunting cartridge there, that is a 200 yard or less (mostly less) round.
Depending on your game, pick the appropriate bullet and then zero the 45-70 in at 100 to 150 yards. With an "external ballistics calculator" you can easily and very accurately calculate, based on your bullet`s BC and velocity, the bullet trajectory in order to determine your cross hair hold over for the longer ranges past your zero or the hold under for shorter ranges closer than your zero. Even if you don`t have a chrony, simply zero in your rifle in at the desired range, then move the target out to 200 yards to see what your bullet drop is.
When you change the loads, charges, bullets and bullet weights, those circles in that BDC reticle don`t move (at least on a Prostaff to my knowledge) and cannot be adjusted to accomodate each loading when there is a trajectory change.
Although some have used them and like the BDC, I have never hunted using a scope with a BDC reticle on either my former 300 Win or my current 300 WSM. Based on knowing my bullet`s BC, MV, which determines the trajectory and with my ARC rangefinder, I`d rather rely on my own judgement with regards to hold over and hold under and simply use a much simpler plex or duplex type reticle.
Your best variabled scopes for the 45-70 would be from a 1x3, 1x4, up to a 1.5x5 max. which have the straight tubes. Or, a fixed power straight tube scope like the 2.5x FX2 would be ideal as well. In closer quarters and for any charging emergency, these scopes offer much better FOV`s and are quicker in acquiring and (both eyes open) aiming to the target than higher powered obj. belled variables. If hunting dangerous bears at the shorter ranges, a split second`s delay can cost substantial lifelong injuries and even death. And, any split second delays in acquiring and aiming speed, can also cause missed shot opportunities on other non-dangerous game as well.
A 45/70 lever carbine, assuming that is what you have, is a handy, quick handling, fast acquiring, shorter range timber and brush gun. You should scope it accordingly to properly match the theme of your rifle.
For shorter to moderate range rifles and cartridges, the above guidelines for scopes are the best choice.
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pyro6999
Optics Retard OT TITAN Joined: December/22/2006 Location: North Dakota Status: Offline Points: 22034 |
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i wouldnt worry about anything past the first circle, and i would double check that its accurate for 200yds, you may have to use the second circle to be on at 200yds
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They call me "Boots"
375H&H Mag: Yeah, it kills stuff "extra dead" 343 we will never forget God Bless Chris Ledoux "good ride cowboy" |
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bbush
Optics Apprentice Joined: October/12/2008 Location: Mississippi Status: Offline Points: 93 |
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I take it that no one knows how many inches Nikon is allowing for each one of the circles below the center. For example, I figured that the first circle is 4 inches, second circle is 8 inches, third circle is 12 inches, or something like that. Well, does anyone know what caliber of rifle Nikon is using as the template to calculate the circles for? |
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cheaptrick
MODERATOR Joined: September/27/2004 Location: South Carolina Status: Offline Points: 20844 |
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Ed Connelly
Optics Retard God of no Chihuahua Joined: December/16/2007 Location: USA Status: Offline Points: 24225 |
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( " Keep it simple, Big Squeeze!! " )
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