I have a leupold vx3l cds scope My hunting changes in altitude between 30m above sea level to over 900m should I pick a in between height for the turret or should I have more than one turret for the same load. I guess what I want to say is how much difference will altitude make to POI at longer ranges as I would normally shoot the same zero at all heights. The scope will be on a .243win and by longer range no further than 500m

I would have one turrent, in MOA, but multiple drop charts.

Any decent ballistic table calculator will allow for altitude to be entered. Just run the numbers and see (and then verify). Let me know if you can't find one.
Peter.

thank you for your time in replying I will look online for a ballistic calculator thanks again

Try this one:

http://www.jbmballistics.com/cgi-bin/jbmtraj-5.1.cgi

see if it gives you what you want.
Peter.

quote:

Originally posted by Peter:
Any decent ballistic table calculator will allow for altitude to be entered. Just run the numbers and see (and then verify). Let me know if you can't find one.
Peter.

Do us all a favor and "then verify" or don't shoot at long range.

I am amazed how many folks think it is as simple as dialing in some numbers after flying or driving hundreds or thousands of miles.

Hey
Less attitude
I'm asking a question.
Of course I would verify. But you have to order these turrets from the US with a long wait and its a 700mile trip up to Scotland.
My question was would I need to order two or more as whether the difference of 1000m in altitude make a change in point of impact at further distance. I already know it makes no change to poi at 200m, I would like to know if it does at longer ranges
Even though I have been stalking for 25 years I have only just started playing at ranges past 250m for no other reason than fun.

Forget the custom knobs. Just buy a target scope, then get some mailing labels. Cut the labels into a thin strip, then attach to the target turret of your scope after verifying drops at various ranges, etc.

Viola, instant custom knobs.

When you get to your new destination, zero at the farthest possible distance. I often shoot at rocks, for example. For example, if you are shooting at 600 yards, dial up to 600, then adjust to be dead on. Make any elevation changes, then undue the set screw and rotate so it is back on the 600 yard mark.

You won't miss at closer ranges.

But to infer going up to 10,000 feet and trusting a custom turret to be on is asking a bit much, IMO.

I shoot 1,000 yards at Butner, NC (about 600 ft. ASL) and Raton, NM ( about 7,000 ft. ASL) and the elevation difference on my .308 with 155 grain bullets is exactly 6 minutes. So at 500 yards with a .243 and half the elevation (ASL) difference I'd say you won't be off more than a couple of minutes. The JBM ballistics calculator mentioned above will tell you for sure.

Another and Clowdis thank you for your responses I looked up the JBM calculator and entered in the info for my rifle and came to the conclusion that I should have just bought a scope with target turrets as well. The CDS just seemed such a good idea at the time. At 500m even if I go for a half way choice altitude I would still be off by 6" at max or min altitude before any error on my part.
I suppose you live and learn anyone want to buy a scope?