how important is adjustable parallax for LR shooting?

[Fenix.NZ]

as the title says..

how necessary is adjustable parallax for Long Range shooting ?

i have found a scope, with the magnifications that i want, but its fixed parallax .. tossing up just getting it anyway but how much of a disadvantage am i going to have if i want to shoot out past 3-400m

 

[ultimate_monkey]

very, my guess the paralax will be set to 100yds, when you get out to 4-500yds that can start to change you POI by inches, so u could land i shot 3"left and one 4" right, or any other direction for that matter and take thre precise out of preceission shooting. the further out you get the worse it will be.

if you have a chance to look threw the scope at objects at a distance, do it, look at somthing 4-5yds away and move your head around slightly, you will notice the x-hairs move all over the place, then look at somthing about 100yds, and move your head around the x hairs will keep the same spot on target

 

[dryfire]

And the greater the magnification the more apparent parallax will be. The reason why high mag. fixed powers and extended mag. range variables have a parallax adjustment.

 

[zimbu]

Actually, the further out your target is the less parallax is a factor. The advantage of AO and side parallax equipped scopes is that they are able to eliminate parallax at closer ranges, i.e. less than 3-400M.

 

[Fenix.NZ]

most adjustable parallax ive seen, once you go over 150 yds then you just turn it up to infinite and you're away..

kind of lends to Zimbu's side of the story

 

[zimbu]

Hold a finger 12" in front of your face and focus across the room. Do a double wink and note the amount of parallax as your finger "jumps" back and forth.
Now do the same with your finger at arms length and you have less parallax. Same principal applies to scopes.

If your scope is set to be parallax free at 200m you won't be shooting bughole groups at 100m with it, but anything beyond 200 you will be fine.

 

[Fenix.NZ]

parallax of the unit im looking at is 100m .. its a 2.5 - 10x magnification .. good all rounder

i wish it did have adjustable parallax, but as long as its goinng to be usable, ill be happy

 

[Bolivar]

Many scopes up to 10X don't have adjustable parallax anyway. The best way for you to find out though is to try it.

Do the eye wobble test at a target out at 3-400 yards and see if the cross hairs jump around.

 

[DILLIGAF]

my 16X vortex scope has paralax adj. from 50 y to 500 and after that is infinity...

 

[Suputin]

As long as you have a good shooting position and can place your eye in the same position for every shot, parallax is not important at all.

 

[Mystic Precision]

Another POV - parallax helps you see the mirage and THAT is critical for my LR shooting.

So I want a high mag scope to have a parallax adjustment - side focus prefered.

I use mine at all distances I shoot which can be beyond 1 mile.

Jerry

 

[Dogleg]

Another POV - parallax helps you see the mirage

You lost me.

 

[Bolivar]

I think he means the parallax adjustment, which also changes the focus of the scope. It can be tweaked to see the mirage at range better to judge wind effects.

 

[brownie]

if you hold your rifle in the same position every shot and look thru the scope the same every time you shoot parallax is not an issue.

 

[Mystic Precision]

I think he means the parallax adjustment, which also changes the focus of the scope. It can be tweaked to see the mirage at range better to judge wind effects.

Yes, by adjusting the focus, I can choose to see the mirage and/or the target clearly.

Jerry

 

[Bolivar]

if you hold your rifle in the same position every shot and look thru the scope the same every time you shoot parallax is not an issue.

That is a couple of big "ifs" I think. Very hard to do, especially from "field" positions like prone, sitting or standing off hand.

 

[LongDraw]

As long as you have a good shooting position and can place your eye in the same position for every shot, parallax is not important at all.

With a fixed Parallax set at 150 yards and you are shooting 400-800 yards or so from various field positions...good luck!

 

[AlexF]

Maximum parallax calculations

It depends on required/desired accuracy.
The maximum parallax error is :
parralax = (objective size / 2) * (target range - parallax free range) / (parallax free range)

For example, 56mm (2") objective 150 yards parallax free range and a target at 1000 yards.
Maximum parallax = (2" / 2) * (1000 - 150) / 150 = 5.66"
This maximum error is more that 1/2 MOA and unacceptable for serious target shooting.

Another example, 40mm (1.675") objective 150 yards parallax free range and a woodchuck at 300 yards.
Maximum parallax = (1.575" /2) * (300 - 150) / 150 = 0.78"
This error is acceptable and should not cause a miss.

You can reach your own conclusions but I think that parallax adjusment is needed if looking at better than 1/2 MOA accuracy.

Alex

 

[Fenix.NZ]

ok ok.. so i can see im going to probably need parallax adjustment for a do all scope..

so who makes a 2-10x scope of good quality with target turrets and side adjustable parallax ?

 

[zimbu]

ok ok.. so i can see im going to probably need parallax adjustment for a do all scope..

so who makes a 2-10x scope of good quality with target turrets and side adjustable parallax ?

http://vortexcanada.net/products/riflescopes/riflescopes.html

The Viper 2.5-10X44 PST looks to be right up your alley.

I have the Viper 6-24X50 PST FFP and it's pretty sweet.