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hunter25's picture
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ballistics and holdover question

Before I ask and before anyone gets started, I will be shooting and checking this out for myself as that is the only way to know for sure. I just won't be able to go shooting for a couple of weeks and wanted to see what everyone thought.

I'm shooting a 7mm remington magnum with 160gr tsx bullets. Leupold 3.5x10 turned up to 10 power. With a 200 yard zero at what range do you think that the point of the  bottom post would also be zeroed?

Never thought about it before.

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Location: Mobile County, Alabama
Joined: 09/09/2007
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A ballistics computing

A ballistics computing program will probably give you a good idea to start with.

 

I like to use "Point Blank" because it's free and easy. Maybe it's still around on the internet some where.

hunter25's picture
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I had actually been using the

I had actually been using the point blank range principle for many years but have decided I would like to be more precise in the future for the longer shots I intend to be practicing with the use of my new range finder.

I have to admit that the old way has always worked fine though.

SSGJB's picture
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 On the Leupold scopes with a

 On the Leupold scopes with a duplex reticles, where the thicker part of the reticle come to a point and continues into a smaller line, from that point to the center of the cross hairs is a 16" difference on 2.5 power at 200yards. So i'm not sure if that will work for you. That is how you can determine the distance using your rifle scope. That's why you have all the numbers on your scope. I don't think it would work the more i think about it. Unless you have pretty close to 16" of drop at what ever yardage your scope is at on 10x. So if you have your scope turned up to 10x directly across from that it should give you a yardage. I think, i hope i didn't lose you?

Don Fischer's picture
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Point blank

I think is the best way to go. Once you get beyond the MPBR of your cartridge your gonna have to start with the holdover. A 7mm mag zeroed at 200yds will probably give you less MPBR and the holdover just starts sooner. No way of getting around the need to hold over. By using another sighting device in the scope is kinda make do. Once you've got the MPBR you can get a trajectory chart out to as far as you want to shoot. If the animal is so far off you have to use holdover, you most likely have time to turn up your elevation adjustment. On my preditor rifle I have the drops at different ranges written an a card and taped to the right side of my butt stock. A simple matter of ranging the target and then making the adjustment needed and then it doesn't matter a whole lot about hold over. Dial it in and hold on the target.

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like so much - it depends

hunter25 wrote:

Before I ask and before anyone gets started, I will be shooting and checking this out for myself as that is the only way to know for sure. I just won't be able to go shooting for a couple of weeks and wanted to see what everyone thought.

I'm shooting a 7mm remington magnum with 160gr tsx bullets. Leupold 3.5x10 turned up to 10 power. With a 200 yard zero at what range do you think that the point of the  bottom post would also be zeroed?

Never thought about it before.

I'm not familar with the Leupold scope cross hairs so I can't answer specifically.  BUt if you were talking about iron sights the answer would depend on how tall the post is.  Different heights of front posts will be dead on target at different heights depending on other things including the height of your rear site.   Another variable not mentioned in your original post is what powder and how much of it you are using to push the projectiles.  5 grains of powder can make quite a difference in point of impact at 200 yards.  Changing powders can make a big difference too. 

You are right on track to take it out and shoot it yourself to find out excatly how allof the variables as relates to your particular rifle with your particular load performs in YOUR hands. 

Good luck and let us know how you make out when you get a chance to get to the range. 

tim
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on my 270 wsm with a 140 gr

on my 270 wsm with a 140 gr accubond with a vx-2 scope.  4x12 lrd reticle.

fromcrosshairs down.  the start of the thick post is 500 yards.  200 yard zero. 

leupold should be able to give you the moa of the difference between the crosshairs and the post.

you can calculate from there.

Don Fischer's picture
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500 yds?

tim wrote:

on my 270 wsm with a 140 gr accubond with a vx-2 scope.  4x12 lrd reticle.

fromcrosshairs down.  the start of the thick post is 500 yards.  200 yard zero. 

leupold should be able to give you the moa of the difference between the crosshairs and the post.

you can calculate from there.

Is that 500 yd number dead on? What happen's at distences between 200 and 500 yards?

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