variable scope ..change of point of impact

[ots03]

I would like to know the reasons of change of point of impact when I move the zoon in a variable,2nd focal plane).
It happens in all the 2nd plane variable scopes?

 

[dmickey]

What brand of variable scope are you using?? Tasco, BSA? That maybe your answer right there!

 

[pepperjones]

if your using a well known brand name scope you can call there tech support and they will tell you what the magnification should be in order to set that scope at, it maybe 10x 12x and so on but the answer to your ? is YES when you zoom in it will change your bullet impact depending on weither you zoom in or out. Sight at a certian power and leave it there. To prove this do the following: place your rifle in a benchrest and stablize it well, now focus on a set target preferrable at a 100 yards with a good paper target, then without moving your rifle in any way, move your zoom in and out and watch what happens. It should slide up and down on the targe verticly. That's why you want to sight and shoot at one known power and not be jumping up and down the scale. That being said it is ok to zoom to look at target like a deer or varmint but alway run it back to the sighted in power to maintain accuracy. Make sense?????

 

[fivering]

A quality variable scope should have very little to no change in bullet impact when using different power settings.

 

[SlowpokeRodriguez]

Just one of many reasons I use only 1st Focal plane glass when I have a choice.

 

[Preacher]

If any of my Nightforces, either NSX or BR's ever start to change impact when I change the power I'll sell em all and put BSA's on em........
What's the sense of more power if you can't use it ?
What happens if your shooting at 42 power and mirage rolls in and you need to reduce the power, but can't because it will change your point of impact ?

 

[Redbarren]

ttt